DOCSLIB.ORG

GGA1-Mediated Endocytic Traffic of LR11/Sorla Alters APP Intracellular Distribution and Amyloid-Β Production Jeremy H

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
GGA1-Mediated Endocytic Traffic of LR11/Sorla Alters APP Intracellular Distribution and Amyloid-Β Production Jeremy H GGA1-mediated endocytic traffic of LR11/SorLA alters APP intracellular distribution and amyloid-β production Jeremy H. Herskowitz, Emory University Katrin Offe, Emory University Aniruddha Deshpande, Emory University Richard A Kahn, Emory University Allan I Levey, Emory University James J Lah, Emory University Journal Title: Molecular Biology of the Cell Volume: Volume 23, Number 14 Publisher: The American Society for Cell Biology | 2012-07-15, Pages 2645-2657 Type of Work: Article | Final Publisher PDF Publisher DOI: 10.1091/mbc.E12-01-0014 Permanent URL: http://pid.emory.edu/ark:/25593/cwsw4 Final published version: http://dx.doi.org/10.1091%2Fmbc.E12-01-0014 Copyright information: © 2012 Herskowitz et al. This is an Open Access work distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License (http://creativecommons.org/licenses/by-nc-sa/3.0/). Accessed October 4, 2021 10:12 AM EDT M BoC | ARTICLE GGA1-mediated endocytic traffic of LR11/SorLA alters APP intracellular distribution and amyloid- β production Jeremy H. Herskowitza, Katrin Offea, Aniruddha Deshpandea, Richard A. Kahnb, Allan I. Leveya, and James J. Laha aCenter for Neurodegenerative Disease, Department of Neurology, and bDepartment of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322 ABSTRACT Proteolytic processing of the amyloid-β precursor protein (APP) and generation Monitoring Editor of amyloid-β peptide (Aβ) are key events in Alzheimer’s disease (AD) pathogenesis. Cell bio- Adam Linstedt logical and genetic evidence has implicated the low-density lipoprotein and sorting receptor Carnegie Mellon University LR11/SorLA in AD through mechanisms related to APP and Aβ production. Defining the cel- Received: Jan 9, 2012 lular pathway(s) by which LR11 modulates Aβ production is critical to understanding how Revised: May 9, 2012 changes in LR11 expression affect the development of Aβ pathology in AD progression. We Accepted: May 16, 2012 report that the LR11 ectodomain is required for LR11-mediated reduction of Aβ and that mutagenesis of the LR11 Golgi-localizing, γ-adaptin ear homology domain, ADP-ribosylation factor (GGA)-binding motif affects the endosomal distribution of LR11, as well as LR11’s ef- fects on APP traffic and βA production. Targeted small interfering RNA (siRNA) knockdown studies of GGA1, GGA2, and GGA3 indicate a surprising degree of specificity toward GGA1, suggesting that GGA1 is a candidate regulator of LR11 traffic. Additional siRNA knockdown experiments reveal that GGA1 is necessary for both LR11 and β-site APP-cleaving enzyme-1 (BACE1) modulation of APP processing to Aβ. Mutagenesis of BACE1 serine 498 to alanine enhances BACE1 targeting to LR11-positive compartments and nullifies LR11-mediated re- duction of Aβ. On basis of these results, we propose that GGA1 facilitates LR11 endocytic traffic and that LR11 modulates Aβ levels by promoting APP traffic to the endocytic recycling compartment. INTRODUCTION The amyloid-β precursor protein (APP) and its derivative, amyloid-β altering APP processing and Aβ production (Goate et al., 1991; peptide (Aβ), play central roles in Alzheimer’s disease (AD). Aβ ac- Citron et al., 1992). To generate Aβ, APP is cleaved by β-secretase/β- cumulates in senile plaques, a pathological hallmark of AD (Masters site of APP-cleaving enzyme-1 (BACE1), resulting in secreted APPβ et al., 1985), and single-gene mutations in APP cause familial AD by (APPsβ) and a carboxyl-terminal fragment (CTFβ), and subsequent action of γ-secretase on CTFβ releases Aβ (Hussain et al., 1999; Sinha and Lieberburg, 1999; Vassar et al., 1999; Wolfe et al., 1999; This article was published online ahead of print in MBoC in Press (http://www Yan et al., 1999; Lin et al., 2000; Xia et al., 2000). Cell biological .molbiolcell.org/cgi/doi/10.1091/mbc.E12-01-0014) on May 23, 2012. studies indicate that APP processing is determined by its intracellu- Address correspondence to: James J. Lah ([email protected]). lar traffic and exposure to secretase enzymes and that βA is pro- Abbreviations used: Aβ, amyloid-β peptide; AD, Alzheimer’s disease; APP, duced in the endosomal compartment, as well as in the early secre- amyloid-β precursor protein; BACE1, β-site APP-cleaving enzyme-1; ELISA, en- zyme-linked immunosorbent assay; GGA, Golgi-localizing, γ-adaptin ear homo- tory pathway (Sisodia, 1992; Koo and Squazzo, 1994; Hartmann logy domain, ADP-ribosylation factor; HEK, human embryonic kidney; LDLR, low- et al., 1997; Xu et al., 1997). density lipoprotein receptor; LR11, low-density lipoprotein receptor with 11 class A ligand-binding repeats. Although specific gene mutations can cause familial AD, the © 2012 Herskowitz et al. This article is distributed by The American Society for Cell causes of sporadic AD remain unclear. The best-established genetic Biology under license from the author(s). Two months after publication it is avail- risk factor is the ɛ4 allele of apolipoprotein E (APOE; Corder et al., able to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). 1993; Strittmatter et al., 1993). Moreover, members of the low-den- “ASCB®,” “The American Society for Cell Biology®,” and “Molecular Biology of sity lipoprotein receptor (LDLR) family, which bind ApoE, have been the Cell®” are registered trademarks of The American Society of Cell Biology. implicated in AD (Okuizumi et al., 1995; Kang et al., 1997; Ma et al., Supplemental Material can be found at: Volume 23 July 15, 2012 http://www.molbiolcell.org/content/suppl/2012/05/19/mbc.E12-01-0014.DC1.html 2645 2002). Low-density lipoprotein receptor with 11 class A ligand-bind- role different LR11 domains play in regulating endogenous APP traf- ing repeats (LR11)/SorLA is a multidomain LDLR family member that fic and βA production in a human cell line. Modified LR11 constructs contains structural elements that also place it in the vacuolar protein demonstrate the essential role of the LR11 ectodomain in redistrib- sorting 10 protein (VPS10p) homology domain family of intracellular uting APP to endosomes and reducing Aβ secretion. Single amino sorting receptors (Jacobsen et al., 1996). We first identified LR11 as acid substitutions in the LR11 GGA-binding domain establish the a transcript that was down-regulated in microarray studies examin- requirement for this motif with respect to LR11 traffic and its effects ing gene expression in patients with AD (Scherzer et al., 2004). Sub- on Aβ production and APP distribution. Targeted small interfering sequently, we demonstrated preferential neuronal loss of LR11 pro- RNA (siRNA) knockdown experiments reveal that GGA1 regulates tein in brain regions vulnerable to AD pathology in sporadic but not LR11 endocytic traffic and that GGA1 is critical for BACE1 and LR11’s familial AD patients, suggesting that LR11 loss plays a specific role effects on endogenous Aβ production. On the basis of these stud- in the pathogenesis of sporadic AD (Scherzer et al., 2004; Dodson ies, we propose that LR11 endocytic traffic, facilitated by GGA1, is et al., 2006). More recent studies indicate early loss of neuronal critical for LR11 modulation of APP traffic and the generation of βA . LR11 in individuals with mild cognitive impairment, a condition that often represents prodromal AD (Sager et al., 2007). Single-nucle- RESULTS otide polymorphisms in noncoding regions of SORL1, the gene en- The LR11 ectodomain is required for LR11-mediated coding LR11, have been linked to AD risk, implying that they influ- Aβ reduction ence disease by altering expression levels rather than by producing To assess the affect of the ectodomain or cytoplasmic tail of LR11 on variant forms of LR11 (Rogaeva et al., 2007). Aβ production, we constructed two chimeras in which the ectodo- Several reports revealed insights into the mechanism by which main or cytoplasmic domain of LR11 was replaced with that of hu- LR11 may influence AD pathogenesis. Overexpression of LR11 re- man LDLR, thus generating LDLR-LR11 and LR11-LDLR, respectively sults in a highly consistent, dose-dependent reduction in APP pro- (Figure 1A). LDLR was chosen because it is in the same lipoprotein cessing to Aβ (Andersen et al., 2005; Offe et al., 2006; Schmidt receptor family as LR11 and was reported to have no effect on APP et al., 2007). Conversely, reduced LR11 expression, as occurs in spo- processing or Aβ levels (Fryer et al., 2005). In addition, we gener- radic AD brain, increases Aβ levels in cultured cells and accelerates ated a construct consisting of the LR11 transmembrane and cyto- amyloid pathology in a transgenic mouse model of AD (Rogaeva plasmic domains but lacking the entire ectodomain (LR11ΔED). All et al., 2007; Dodson et al., 2008; Rohe et al., 2008). LR11 interacts constructs were epitope tagged with V5 at the N-termini. with APP, and colocalization between these proteins has been ob- To investigate effects on APP processing and Aβ production, we served in endosomal and Golgi compartments in multiple cell types, transiently expressed LR11 constructs in human embryonic kidney including primary neurons (Andersen et al., 2005; Offe et al., 2006; (HEK) 293 cells. This cell line was chosen due to the ability to detect Spoelgen et al., 2006). LR11 is a large transmembrane protein, and endogenous APP protein by immunoblot and secreted Aβ by en- its domain structure indicates that it may act as an endocytic cell zyme-linked immunosorbent assay (ELISA), and our standard trans- surface receptor and as an intracellular sorting receptor (Jacobsen fection efficiency is ∼60% under these conditions. Cell extracts and et al., 1996, 2001, 2002). The LR11 ectodomain harbors a cluster of conditioned media were assayed for endogenous full-length APP 11 type A ligand-binding repeats and a Vps10p homology domain and α-secretase cleaved APPs, respectively, by immunoblotting, (Jacobsen et al., 1996; Yamazaki et al., 1996), and the LR11 cyto- and secreted Aβ1-40 was detected by sandwich ELISA.
Load more

Recommended publications
  • BACE1 Function and Inhibition: Implications of Intervention in the Amyloid Pathway of Alzheimer’S Disease Pathology
    Review BACE1 Function and Inhibition: Implications of Intervention in the Amyloid Pathway of Alzheimer’s Disease Pathology Gerald Koelsch CoMentis, Inc., South San Francisco, CA 94080, USA; [email protected] Received: 15 September 2017; Accepted: 10 October 2017; Published: 13 October 2017 Abstract: Alzheimer’s disease (AD) is a fatal progressive neurodegenerative disorder characterized by increasing loss in memory, cognition, and function of daily living. Among the many pathologic events observed in the progression of AD, changes in amyloid β peptide (Aβ) metabolism proceed fastest, and precede clinical symptoms. BACE1 (β-secretase 1) catalyzes the initial cleavage of the amyloid precursor protein to generate Aβ. Therefore inhibition of BACE1 activity could block one of the earliest pathologic events in AD. However, therapeutic BACE1 inhibition to block Aβ production may need to be balanced with possible effects that might result from diminished physiologic functions BACE1, in particular processing of substrates involved in neuronal function of the brain and periphery. Potentials for beneficial or consequential effects resulting from pharmacologic inhibition of BACE1 are reviewed in context of ongoing clinical trials testing the effect of BACE1 candidate inhibitor drugs in AD populations. Keywords: Alzheimer’s disease; amyloid hypothesis; BACE1; beta secretase; pharmacology 1. Introduction Alzheimer’s disease (AD) is a fatal progressive neurodegenerative disorder, slowly eroding memory, cognition, and functions of daily living, inevitably culminating in death from pneumonia and infectious diseases resulting from failure to thrive, loss of fine motor skills, and incapacitation. Treatment is limited to therapeutics that alleviate symptoms of memory loss, but are effective for a relatively short duration during and after which disease progression continues.
    [Show full text]
  • Rabbit Anti-RABEP1 Antibody-SL19721R
    SunLong Biotech Co.,LTD Tel: 0086-571- 56623320 Fax:0086-571- 56623318 E-mail:[email protected] www.sunlongbiotech.com Rabbit Anti-RABEP1 antibody SL19721R Product Name: RABEP1 Chinese Name: RABEP1蛋白抗体 Neurocrescin; Rab GTPase binding effector protein 1; RAB5EP; Rabaptin 4; Rabaptin Alias: 5; Rabaptin 5alpha; RABPT5; RABPT5A; Renal carcinoma antigen NY REN 17; Renal carcinoma antigen NYREN17. Organism Species: Rabbit Clonality: Polyclonal React Species: Human,Mouse,Rat, ELISA=1:500-1000IHC-P=1:400-800IHC-F=1:400-800ICC=1:100-500IF=1:100- 500（Paraffin sections need antigen repair） Applications: not yet tested in other applications. optimal dilutions/concentrations should be determined by the end user. Molecular weight: 99kDa Cellular localization: The cell membrane Form: Lyophilized or Liquid Concentration: 1mg/ml immunogen: KLH conjugated synthetic peptide derived from human RABEP1:501-600/862 Lsotype: IgGwww.sunlongbiotech.com Purification: affinity purified by Protein A Storage Buffer: 0.01M TBS(pH7.4) with 1% BSA, 0.03% Proclin300 and 50% Glycerol. Store at -20 °C for one year. Avoid repeated freeze/thaw cycles. The lyophilized antibody is stable at room temperature for at least one month and for greater than a year Storage: when kept at -20°C. When reconstituted in sterile pH 7.4 0.01M PBS or diluent of antibody the antibody is stable for at least two weeks at 2-4 °C. PubMed: PubMed RABEP1 is a Rab effector protein acting as linker between gamma-adaptin, RAB4A and RAB5A. It is involved in endocytic membrane fusion and membrane trafficking of Product Detail: recycling endosomes. Stimulates RABGEF1 mediated nucleotide exchange on RAB5A.
    [Show full text]
  • Sequence and Comparative Analysis of the Chicken Genome Provide Unique Perspectives on Vertebrate Evolution
    articles Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution International Chicken Genome Sequencing Consortium* *Lists of participants and affiliations appear at the end of the paper ........................................................................................................................................................................................................................... We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome—composed of approximately one billion base pairs of sequence and an estimated 20,000–23,000 genes—provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture. Genome sequence comparison is a modern extension of the long- standing use of other species as models to illuminate aspects of human biology and medicine. Large-scale genome analyses also highlight the evolutionary dynamics of selective and mutational processes at different chronological scales1–4. We present here results obtained from an extensive analysis of a draft sequence of the chicken genome, which has evolved separately from mammalian genomes for ,310 million years (Myr)4,5 (Fig.
    [Show full text]
  • Analysis of Gga Null Mice Demonstrates a Non- Redundant Role for Mammalian GGA2 During Development
    Analysis of Gga Null Mice Demonstrates a Non- Redundant Role for Mammalian GGA2 during Development Jennifer Govero., Balraj Doray., Hongdong Bai¤, Stuart Kornfeld* Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America Abstract Numerous studies using cultured mammalian cells have shown that the three GGAs (Golgi-localized, gamma-ear containing, ADP-ribosylation factor- binding proteins) function in the transport of cargo proteins between the trans- Golgi network and endosomes. However, the in vivo role(s) of these adaptor proteins and their possible functional redundancy has not been analyzed. In this study, the genes encoding GGAs1-3 were disrupted in mice by insertional mutagenesis. Loss of GGA1 or GGA3 alone was well tolerated whereas the absence of GGA2 resulted in embryonic or neonatal lethality, depending on the genetic background of the mice. Thus, GGA2 mediates a vital function that cannot be compensated for by GGA1and/or GGA3. The combined loss of GGA1 and GGA3 also resulted in a high incidence of neonatal mortality but in this case the expression level of GGA2 may be inadequate to compensate for the loss of the other two GGAs. We conclude that the three mammalian GGAs are essential proteins that are not fully redundant. Citation: Govero J, Doray B, Bai H, Kornfeld S (2012) Analysis of Gga Null Mice Demonstrates a Non-Redundant Role for Mammalian GGA2 during Development. PLoS ONE 7(1): e30184. doi:10.1371/journal.pone.0030184 Editor: Ludger Johannes, Institut Curie, France Received October 27, 2011; Accepted December 15, 2011; Published January 26, 2012 Copyright: ß 2012 Govero et al.
    [Show full text]
  • Mouse Gga1 Conditional Knockout Project (CRISPR/Cas9)
    https://www.alphaknockout.com Mouse Gga1 Conditional Knockout Project (CRISPR/Cas9) Objective: To create a Gga1 conditional knockout Mouse model (C57BL/6J) by CRISPR/Cas-mediated genome engineering. Strategy summary: The Gga1 gene (NCBI Reference Sequence: NM_145929 ; Ensembl: ENSMUSG00000033128 ) is located on Mouse chromosome 15. 17 exons are identified, with the ATG start codon in exon 1 and the TAG stop codon in exon 17 (Transcript: ENSMUST00000041587). Exon 2~3 will be selected as conditional knockout region (cKO region). Deletion of this region should result in the loss of function of the Mouse Gga1 gene. To engineer the targeting vector, homologous arms and cKO region will be generated by PCR using BAC clone RP24-83M14 as template. Cas9, gRNA and targeting vector will be co-injected into fertilized eggs for cKO Mouse production. The pups will be genotyped by PCR followed by sequencing analysis. Note: Mice homozygous for a gene-trapped allele display decreased birth weight, slow postnatal weight gain, hypoglycemia, increased plasma levels of acid hydrolases, and partial neonatal lethality. Exon 2 starts from about 2.31% of the coding region. The knockout of Exon 2~3 will result in frameshift of the gene. The size of intron 1 for 5'-loxP site insertion: 3420 bp, and the size of intron 3 for 3'-loxP site insertion: 1064 bp. The size of effective cKO region: ~1666 bp. The cKO region does not have any other known gene. Page 1 of 8 https://www.alphaknockout.com Overview of the Targeting Strategy Wildtype allele 5' gRNA region gRNA region 3' 1 2 3 4 5 17 Targeting vector Targeted allele Constitutive KO allele (After Cre recombination) Legends Exon of mouse Gga1 Homology arm cKO region loxP site Page 2 of 8 https://www.alphaknockout.com Overview of the Dot Plot Window size: 10 bp Forward Reverse Complement Sequence 12 Note: The sequence of homologous arms and cKO region is aligned with itself to determine if there are tandem repeats.
    [Show full text]
  • GGA1 (D-6): Sc-271927
    SANTA CRUZ BIOTECHNOLOGY, INC. GGA1 (D-6): sc-271927 BACKGROUND APPLICATIONS The GGA family of proteins (Golgi-localized, g-adaptin ear-containing, ARF- GGA1 (D-6) is recommended for detection of GGA1 of human origin by binding proteins) are ubiquitous coat proteins that facilitate the trafficking Western Blotting (starting dilution 1:100, dilution range 1:100-1:1000), of soluble proteins from the trans-Golgi network (TGN) to endosomes/lyso- immunoprecipitation [1-2 µg per 100-500 µg of total protein (1 ml of cell somes by means of interactions with TGN-sorting receptors, ARF (ADP-ribo- lysate)], immunofluorescence (starting dilution 1:50, dilution range 1:50- sylation factor) and Clathrin. Members of the GGA family, GGA1, GGA2 (also 1:500), immunohistochemistry (including paraffin-embedded sections) known as VEAR) and GGA3, are multidomain proteins that bind mannose 6- (starting dilution 1:50, dilution range 1:50-1:500) and solid phase ELISA phosphate receptors (MPRs). GGAs have modular structures with an N-termi- (starting dilution 1:30, dilution range 1:30-1:3000). nal VHS (VPS-27, Hrs and STAM) domain followed by a GAT (GGA and TOM1) Suitable for use as control antibody for GGA1 siRNA (h): sc-41167, GGA1 domain, a connecting hinge segment and a C-terminal GAE ( -adaptin ear) g shRNA Plasmid (h): sc-41167-SH and GGA1 shRNA (h) Lentiviral Particles: domain. The amino-terminal VHS domains of GGAs form complexes with sc-41167-V. the cytoplasmic domains of sorting receptors by recognizing acidic-cluster di-leucine (ACLL) sequences. GGA1 and GGA2 do not associate with each Molecular Weight of GGA1: 85 kDa.
    [Show full text]
  • Association Between GGA1 Gene Polymorphisms and Occurrence of Mammary Mixed Tumors and Aging in Domestic Bitches1)
    34 Med. Weter. 2016, 72 (1), 34-40 Praca oryginalna Original paper Association between GGA1 gene polymorphisms and occurrence of mammary mixed tumors and aging in domestic bitches1) WIESŁAWA KRANC*, ADRIAN CHACHUŁA**, KATARZYNA WOJTANOWICZ-MARKIEWICZ***, KATARZYNA ZAORSKA**, EDYTA OCIEPA***, ADAM PIOTROWSKI*, DOROTA BUKOWSKA***, SYLWIA CIESIÓŁKA**, SYLWIA BORYS****, HANNA PIOTROWSKA****, AGNIESZKA SKOWROŃSKA*****, MARCIN NOWAK******, PAWEŁ ANTOSIK***, KLAUS-PETER BRÜSSOW***, BARTOSZ KEMPISTY*, **, MAŁGORZATA BRUSKA*, MICHAŁ NOWICKI**, MACIEJ ZABEL**, ******* *Department of Anatomy, **Department of Histology and Embryology, Medicine Faculty I, Poznan University of Medical Sciences, Swiecickiego 6 St., 60-781 Poznan, Poland ***Institute of Veterinary Sciences, Faculty of Animal Breeding and Biology, Poznan University of Life Sciences, Wolynska 35 St., 60-637 Poznan, Poland ****Department of Toxicology, Faculty of Farmacy, Poznan University of Medical Sciences, Dojazd 30 St., 60-631 Poznan, Poland *****Department of Human Physiology, Faculty of Medical Sciences, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland ******Department of Pathology, Faculty of Veterinary Medicine, Wroclaw University of Life Sciences, C. K. Norwida 31 St., 50-375 Wrocław, Poland *******Department of Histology and Embryology, Wroclaw Medical University, 6a Chalubinskiego St., 50-368, Wroclaw, Poland Received 13.07.2015 Accepted 03.11.2015 Kranc W., Chachuła A., Wojtanowicz-Markiewicz K., Zaorska K., Ociepa E., Piotrowski A., Bukowska D., Ciesiółka S., Borys S., Piotrowska H., Skowrońska A., Nowak M., Antosik P., Brüssow K.-P., Kempisty B., Bruska M., Nowicki M., Zabel M. Association between GGA1 gene polymorphisms and occurrence of mammary mixed tumours and aging in domestic bitches Summary In recent years the number of malignant mammary gland tumor occurrences in domestic bitches has increased.
    [Show full text]
  • Genome-Wide Association Study Reveals Putative Role of Gga-Mir
    Yuan et al. BMC Genomics (2017) 18:699 DOI 10.1186/s12864-017-4092-9 ORIGINALPAPER Open Access Genome-wide association study reveals putative role of gga-miR-15a in controlling feed conversion ratio in layer chickens Jingwei Yuan1, Sirui Chen1, Fengying Shi2, Guiqin Wu2, Aiqiao Liu2, Ning Yang1 and Congjiao Sun1* Abstract Background: Efficient use of feed resources for farm animals is a critical concern in animal husbandry. Numerous genetic and nutritional studies have been conducted to investigate feed efficiency during the regular laying cycle of chickens. However, by prolonging the laying period of layers, the performance of feed utilization in the late- laying period becomes increasingly important. In the present study, we measured daily feed intake (FI), residual feed intake (RFI) and feed conversion ratio (FCR) of 808 hens during 81–82 weeks of age to evaluate genetic properties and then used a genome-wide association study (GWAS) to reveal the genetic determinants. Results: The heritability estimates for the investigated traits were medium and between 0.15 and 0.28 in both pedigree- and genomic-based estimates, whereas the genetic correlations among these traits were high and ranged from 0.49 to 0.90. Three genome-wide significant SNPs located on chromosome 1 (GGA1) were detected for FCR. Linkage disequilibrium (LD) and conditional GWA analysis indicated that these 3 SNPs were highly correlated with one another, located at 13.55–45.16 Kb upstream of gga-miR-15a. Results of quantitative real-time polymerase chain reaction (qRT-PCR) analysis in liver tissue showed that the expression of gga-miR-15a was significantly higher in the high FCR birds than that in the medium or low FCR birds.
    [Show full text]
  • Review the Sorting and Trafficking of Lysosomal Proteins
    Histol Histopathol (2006) 21: 899-913 Histology and http://www.hh.um.es Histopathology Cellular and Molecular Biology Review The sorting and trafficking of lysosomal proteins X. Ni, M. Canuel and C.R. Morales Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada Summary. For a long time lysosomes were considered phosphate, to allow its recognition by a sorting receptor. terminal organelles involved in the degradation of Protein sorting in most eukaryotic cells may also involve different substrates. However, this view is rapidly protein-protein interactions between the cargo and the changing by evidence demonstrating that these receptor. Consequently, eukaryotic cells may have an organelles and their content display specialized functions additional repertoire of receptors that recognize amino in addition to the degradation of substances. Many acid sequences and/or motifs in the lysosomal cargo. lysosomal proteins have been implicated in specialized Such motifs have the property to specify the sorting and cellular functions and disorders such as antigen final destination of the cargo. This possibility is processing, targeting of surfactant proteins, and most discussed in the present review. lysosomal storage disorders. To date, about fifty To exit a sorting compartment a receptor must lysosomal hydrolases have been identified, and the interact with cytoplasmic coat proteins such as adaptor majority of them are targeted to the lysosomes via the proteins, ARF and clathrin, that cause vesicles to bud mannose-6-phosphate receptor (M6P-Rc). However, from donor membranes (trans-Golgi network/TGN) and recent studies on the intracellular trafficking of the non- to traffic to acceptor membranes (late endosomes and enzymic lysosomal proteins prosaposin and GM2 lysosomes).
    [Show full text]
  • Genetic Architecture of Bone Quality Variation in Layer Chickens Revealed
    www.nature.com/scientificreports OPEN Genetic architecture of bone quality variation in layer chickens revealed by a genome-wide association Received: 26 October 2016 Accepted: 23 February 2017 study Published: 06 April 2017 Jun Guo1,*, Congjiao Sun2,*, Liang Qu1, Manman Shen1, Taocun Dou1, Meng Ma1, Kehua Wang1 & Ning Yang2 Skeletal problems in layer chickens are gaining attention due to animal welfare and economic losses in the egg industry. The genetic improvement of bone traits has been proposed as a potential solution to these issues; however, genetic architecture is not well understood. We conducted a genome-wide association study (GWAS) on bone quality using a sample of 1534 hens genotyped with a 600 K Chicken Genotyping Array. Using a linear mixed model approach, a novel locus close to GSG1L, associated with femur bone mineral density (BMD), was uncovered in this study. In addition, nine SNPs in genes were associated with bone quality. Three of these genes, RANKL, ADAMTS and SOST, were known to be associated with osteoporosis in humans, which makes them good candidate genes for osteoporosis in chickens. Genomic partitioning analysis supports the fact that common variants contribute to the variations of bone quality. We have identified several strong candidate genes and genomic regions associated with bone traits measured in end-of-lay cage layers, which accounted for 1.3–7.7% of the phenotypic variance. These SNPs could provide the relevant information to help elucidate which genes affect bone quality in chicken. Osteoporosis in hens is a common disease leading to increased risk to bone fracture, and is especially severe in caged layer populations, yet the underlying genetic architecture is poorly understood.
    [Show full text]
  • Role of the Polycystins in Cell Migration, Polarity, and Tissue Morphogenesis
    Cells 2015, 4, 687-705; doi:10.3390/cells4040687 OPEN ACCESS cells ISSN 2073-4409 www.mdpi.com/journal/cells Review Role of the Polycystins in Cell Migration, Polarity, and Tissue Morphogenesis Elisa Agnese Nigro, Maddalena Castelli and Alessandra Boletta * Division of Genetics and Cell Biology, Dibit, IRCCS-San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milano, Italy; E-Mails: [email protected] (E.A.N.); [email protected] (M.C.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +39-02-2643-4805; Fax: +39-02-2643-4861. Academic Editor: Christoph Englert Received: 7 August 2015 / Accepted: 26 October 2015 / Published: 30 October 2015 Abstract: Cystic kidney diseases (CKD) is a class of disorders characterized by ciliary dysfunction and, therefore, belonging to the ciliopathies. The prototype CKD is autosomal dominant polycystic kidney disease (ADPKD), whose mutated genes encode for two membrane-bound proteins, polycystin-1 (PC-1) and polycystin-2 (PC-2), of unknown function. Recent studies on CKD-associated genes identified new mechanisms of morphogenesis that are central for establishment and maintenance of proper renal tubular diameter. During embryonic development in the mouse and lower vertebrates a convergent-extension (CE)-like mechanism based on planar cell polarity (PCP) and cellular intercalation is involved in “sculpting” the tubules into a narrow and elongated shape. Once the appropriate diameter is established, further elongation occurs through oriented cell division (OCD). The polycystins (PCs) regulate some of these essential processes. In this review we summarize recent work on the role of PCs in regulating cell migration, the cytoskeleton, and front-rear polarity.
    [Show full text]
  • GGA2 Interacts with EGFR Cytoplasmic Domain to Stabilize The
    www.nature.com/scientificreports Corrected: Author Correction OPEN GGA2 interacts with EGFR cytoplasmic domain to stabilize the receptor expression and promote Received: 23 August 2017 Accepted: 3 January 2018 cell growth Published online: 22 January 2018 Takefumi Uemura1, Satoshi Kametaka2 & Satoshi Waguri1 Epidermal growth factor receptor (EGFR) signaling and its downregulation upon ligand binding have been extensively documented. However, the mechanisms by which cells maintain steady-state EGFR expression remain poorly understood. Here, we report a novel role of Golgi-localized, γ-adaptin ear- containing, ADP ribosylation factor-binding protein 2 (GGA2) in the control of EGFR turnover. Whereas GGA1- or GGA3-depletion increased EGFR expression, GGA2-depletion by RNAi greatly reduced steady-state expression of EGFR, refecting enhanced lysosomal degradation of EGFR. Subsequent pull-down assays showed interactions of VHS-GAT domains from three GGAs with the cytoplasmic juxtamembrane region (jxt) of EGFR, which was dependent on N108 in the VHS domain. Proximity ligation assay also revealed the steady-state interaction between GGA2 and EGFR in situ. Moreover, reduced expression of EGFR in GGA2-depleted cells was reversed by additional depletion of GGA1 or GGA3, suggesting that GGA1 and GGA3 promote EGFR degradation. In addition, GGA2-depleted cells had reduced EGF signaling and cell proliferation in cell culture and xenograft experiments. Finally, GGA2 was upregulated in 30.8% of human hepatocellular carcinomas and 23.3% of colorectal cancers. Together, these results indicate that GGA2 supports cell growth by interacting with EGFR for sustaining the receptor expression. Epidermal growth factor receptor (EGFR; also known as ErbB1 or Her1) is a receptor tyrosine kinase (RTK) that is involved in eukaryotic development and cancer pathogenesis1.
    [Show full text]