A Novel Class of Miniature Inverted Repeat Transposable Elements (Mites) That Contain Hitchhiking (GTCY)N Microsatellites

Total Page:16

File Type:pdf, Size:1020Kb

A Novel Class of Miniature Inverted Repeat Transposable Elements (Mites) That Contain Hitchhiking (GTCY)N Microsatellites Insect Molecular Biology Insect Molecular Biology (2011) 20(1), 15–27 doi: 10.1111/j.1365-2583.2010.01046.x A novel class of miniature inverted repeat transposable elements (MITEs) that contain hitchhiking (GTCY)n microsatellites B. S. Coates*, J. A. Kroemer*, D. V. Sumerford*† and Gutman, 1987). PCR-based molecular genetic markers R. L. Hellmich*† are often designed to assay for fragment-size variation *USDA-ARS, Corn Insects & Crop Genetics Research amongst alleles at microsatellite loci, and rely on unique Unit, Genetics Laboratory; and †Department of DNA sequence flanking independent tandem repeats to Entomology, Iowa State University, Ames, IA, USA attain locus specificity (Tautz, 1989; Weber & May, 1989). In contrast, instances occur when PCR amplification prod- ucts are weak or contain unintended background frag- Abstractimb_1046 15..27 ments derived from >1 locus (Economou et al., 1990). The movement of miniature inverted repeat transpos- Genotypes are difficult to determine correctly from these able elements (MITEs) modifies genome structure and problematic loci, and analysis of data often result in devia- function. We describe the microsatellite-associated tions from Hardy–Weinberg equilibrium within natural interspersed nuclear element 2 (MINE-2), that inte- populations and Mendelian expectations within pedigrees grates at consensus WTTTT target sites, creates (Terro et al., 2006). Analogous difficulties are often dinucleotide TT target site duplications (TSDs), and encountered when microsatellite markers are developed forms predicted MITE-like secondary structures; a 5Ј for species of Lepidoptera (Anthony et al., 2001; Meglécz subterminal inverted repeat (SIR; AGGGTTCCGTAG) et al., 2004), and may in part be affected by the movement that is partially complementary to a 5Ј inverted repeat of transposable elements (TEs; Coates et al., 2009, (IR; ACGAAGCCCT) and 3Ј-SIRs (TTACGGAACCCT). 2010). A (GTCY)n microsatellite is hitchhiking downstream of Transposable elements are portions of genome DNA conserved 5Ј MINE-2 secondary structures, causing capable of ‘jumping’ amongst loci, and can affect microsat- flanking sequence similarity amongst mobile micro- ellites by inserting in proximity or by carrying hitchhiking satellite loci. Transfection of insect cell lines indicates microsatellites within the TE itself (Chen & Li, 2007; Yang & that MITE-like secondary structures are sufficient to Barbash, 2008; Coates et al., 2009, 2010). Miniature mediate genome integration, and provides insight into inverted-repeat TEs (MITEs) are class II TEs that use a the transposition mechanism used by MINE-2s. ‘cut-and-paste’ mechanism to move a DNA segment amongst loci, and are nonreplicative as a result of the Keywords: transposons, repetitive element, PCR excision of the entire MITE and subsequent reinsertion at competition. different genome locations (Craig, 1995). MITEs have characteristic hairpin-like secondary structures that include Introduction terminal inverted repeats (TIRs; Wessler et al., 1995) or Microsatellites are composed of short nucleotide units subterminal inverted repeats (SIRs) that may be required repeated in tandem, and can show allelic size variation for recognition by enzymes that facilitate their mobility (Tu because of the addition or deletion of repeat units by slip & Orphanidis, 2001). As a result of a lack of protein coding strand mispairing during DNA replication (Levinson & sequence, MITEs are small in size (100 to 600 bp) and are referred to as non-autonomous TEs because movement depends upon the function of enzymes encoded within First published online 24 October 2010. ancestral autonomous TEs (MacRae & Clegg, 1992). Thus, Correspondence: Brad S. Coates, USDA-ARS, Corn Insects & Crop MITEs are hypothesized to result from deletions within Genetics Research, 113 Genetics Lab, Iowa State University, Ames, IA 50010, USA. Tel.: + 1 515 294 0668; fax: + 1 515 294 2265; e-mail: ancestral autonomous TEs or fortuitous proximity of juxta- [email protected] posed TIRs within the genome (Tsubota & Huong, 1991; © 2010 The Authors Insect Molecular Biology © 2010 The Royal Entomological Society 15 16 B. S. Coates et al. MacRae & Clegg, 1992). These autonomous TE-encoded integration of MINE-2 elements into insect cell lines, which enzymes are dual-function, and act as both an endonu- suggests that sequence within these regions is conserved clease and integrase during excision (‘cut’) and integration as a result of the requirement for active transposition. (‘paste’), respectively. The integrase functions in site- specific recognition ofa4to5bpgenome sequence that is Results and discussion followed by endonuclease-mediated cleavage that leaves a pair of nucleotide overhangs at the site of integration, and Annotation of MITE-like sequence and secondary is analogous to type II restriction enzymes commonly used structural features in molecular biology applications (Roberts, 2005). Follow- Although gene coding regions are important for cellular ing insertion of the MITE into the cut site, the nucleotide functions, the movement of TEs within a genome is known overhangs are filled in by DNA polymerase, which results in to cause chromosomal changes and alterations in gene sequence duplication flanking the TE, and are referred to expression (Kidwell & Lisch, 2001; Eichler & Sankoff, as the target site duplications (TSDs). Excision is essen- 2003; Kazazian, 2004; Feschotte & Pritham, 2007; tially integration in reverse, and results in the ‘cutting’ of the Feschotte, 2008). Knowledge of the type and number of MITE from a genome location for eventual reinsertion into TEs in a genome is fundamental to the study of changes another genome location. As movement is nonreplicative in genome structure, function and adaptation, and is a the entire MITE ‘jumps’ from an existing integration posi- critical initial step in order to define future comparative tion, but indications of past TE inserts remain because of studies. A 555 bp sequence was previously described retention of the TSD (Dawid & Rebbert, 1981). within an exon of the Helicoverpa zea cyp321A2 gene Nonreplicative ‘cut-and-paste’ movement may pose a (GenBank accession no. DQ788841 in Fig. 1) and was quandary as to how MITEs increase copy number within a annotated as a retroelement-like short interspersed genome. This propagation is shown to occur indirectly nuclear element (SINE; Chen & Li, 2007). This annotation through DNA gap repair and DNA replication events. In the was based upon the observation of AAAAA sequences 5′ first instance, MITE excision from one homologous chro- and 3′ of the integrated TE, which were assumed to rep- mosome pair in a diploid organism can invoke the DNA resent target site duplications (TSDs) similar to those gap repair mechanism, causing restoration of the MITE generated by Bos taurus (Szemraj et al., 1995) and Gallus when present upon the homologous chromosome. Simi- gallus retroelements (Salva & Birch, 1989). This TE was larly, DNA gap repair acts upon a sister chromatid when subsequently referred to as HzSINE1 (Chen & Li, 2007). MITE integration occurs at a novel genome haplotype SINEs are class I non-long terminal repeat (non-LTR) TEs location, where the newly integrated TE is used as tem- that propagate or make copies of themselves by a repli- plate for repair (Engels et al., 1990). A second method cative mechanism that uses an RNA intermediate tran- takes place during DNA replication, when a MITE excises scribed from the SINE itself (Weiner, 2002). The 5′ regions from the newly replicated strand with subsequent of SINEs retain homology to tRNA, 5S rRNA or 7SL RNA- re-integration at novel positions within the parental strand like genes from which they were derived (Okada, 1991; leading to a net MITE copy number gain (Ros & Kunze, 2001). These methods of MITE propagation have contrib- uted to the proliferation of hitchhiking microsatellites within genomes of the insect species Ostrinia nubilalis (Coates et al., 2009), and Drosophila sp. (Locke et al., 1999; Vivas et al., 1999; Miller et al., 2000; Wilder & Hollocher, 2001; Yang et al., 2006; Yang & Barbash, 2008). Despite initial descriptions, the extent to which propagation of MITE-like elements have contributed to the proliferation of microsat- ellite loci within the genomes of Lepidoptera remain largely unknown. To partially address this question, we herein describe a novel group of MITEs called the microsatellite-associated interspersed nuclear element family 2 (MINE-2), that contain an internal hitchhiking Figure 1. Amplification and expression of Helicoverpa zea short (GTCY)n microsatellite. Evidence suggests that MINE-2 interspersed nuclear element 1 [HzSINE1; H. zea microsatellite- elements are conserved within the genomes of Lepi- associated interspersed nuclear element 2 (HzMINE-2)] from (A) doptera, and sequence immediately flanking the (GTCY)n genomic DNA (gDNA) for the 555 bp HzSINE1 (HzMINE-2) and microsatellite is highly conserved as a result of involve- ~1250 bp ribosomal protein small subunit 13 (rpS13) gene products. (B) mRNA-enriched and mRNA subtracted pools from larvae under ment in the formation of TIR and IR structures. These normal growth conditions (n; 27 °C) and heat shock conditions secondary structures are shown to facilitate the stable (h; 48 °C for 30 min). © 2010 The Authors Insect Molecular Biology © 2010 The Royal Entomological Society, 20, 15–27 Lepidopteran mobile microsatellites 17 Frenkel et al., 2003), and the region includes an RNA Lack of an RNA pol III promoter.
Recommended publications
  • Specific Binding of Transposase to Terminal Inverted Repeats Of
    Proc. Natl. Acad. Sci. USA Vol. 84, pp. 8220-8224, December 1987 Biochemistry Specific binding of transposase to terminal inverted repeats of transposable element Tn3 (transposon/DNA binding protein/DNase I "footprinting") HITOSHI ICHIKAWA*, KAORU IKEDA*, WILLIAM L. WISHARTt, AND EIICHI OHTSUBO*t *Institute of Applied Microbiology, University of Tokyo, Bunkyo-ku, Yayoi 1-1-1, Tokyo 113, Japan; and tDepartment of Molecular Biology, Princeton University, Princeton, NJ 08544 Communicated by Norman Davidson, July 27, 1987 ABSTRACT Tn3 transposase, which is required for trans- containing the Tn3 terminal regions when 8 mM ATP is position of Tn3, has been purified by a low-ionic-strength- present (14). precipitation method. Using a nitrocellulose filter binding In this paper, we study the interaction of Tn3 transposase, assay, we have shown that transposase binds to any restriction which has been purified by a low-ionic-strength-precipitation fragment. However, binding of the transposase to specific method, with DNA. We demonstrate that the purified fragments containing the terminal inverted repeat sequences of transposase is an ATP-independent DNA binding protein, Tn3 can be demonstrated by treatment of transposase-DNA which has interesting properties that may be involved in the complexes with heparin, which effectively removes the actual transposition event of Tn3. transposase bound to the other nonspecific fragments at pH 5-6. DNase I "footprinting" analysis showed that the MATERIALS AND METHODS transposase protects an inner 25-base-pair region of the 38- base-pair terminal inverted repeat sequence of Tn3. This Bacterial Strains and Plasmids. The bacterial strains used protection is not dependent on pH.
    [Show full text]
  • Retrotransposon- and Microsatellite Sequence-Associated Genomic Changes in Early Generations of a Newly Synthesized Allotetraploid Cucumis 3 Hytivus Chen & Kirkbride
    Plant Mol Biol DOI 10.1007/s11103-011-9804-y Retrotransposon- and microsatellite sequence-associated genomic changes in early generations of a newly synthesized allotetraploid Cucumis 3 hytivus Chen & Kirkbride Biao Jiang • Qunfeng Lou • Zhiming Wu • Wanping Zhang • Dong Wang • Kere George Mbira • Yiqun Weng • Jinfeng Chen Received: 27 May 2011 / Accepted: 27 June 2011 Ó Springer Science+Business Media B.V. 2011 Abstract Allopolyploidization is considered an essential generations of a newly synthesized allotetraploid Cucum- evolutionary process in plants that could trigger genomic is 9 hytivus Chen & Kirkbride (2n = 4x = 38) which was shock in allopolyploid genome through activation of tran- derived from crossing between cultivated cucumber scription of retrotransposons, which may be important in C. sativus L. (2n = 2x = 14) and its wild relative C. hystrix plant evolution. Two retrotransposon-based markers, inter- Chakr. (2n = 2x = 24). Extensive genomic changes were retrotransposon amplified polymorphism and retro- observed, most of which involved the loss of parental DNA transposon-microsatellite amplified polymorphism and a fragments and gain of novel fragments in the allotetraploid. microsatellite-based marker, inter simple sequence repeat Among the 28 fragments examined, 24 were lost while four were employed to investigate genomic changes in early were novel, suggesting that DNA sequence elimination is a relatively frequent event during polyploidization in Cucumis. Interestingly, of the 24 lost fragments, 18 were of C. hystrix origin, four were C. sativus-specific, and the Electronic supplementary material The online version of this remaining two were shared by both species, implying that article (doi:10.1007/s11103-011-9804-y) contains supplementary material, which is available to authorized users.
    [Show full text]
  • Complete Article
    The EMBO Journal Vol. I No. 12 pp. 1539-1544, 1982 Long terminal repeat-like elements flank a human immunoglobulin epsilon pseudogene that lacks introns Shintaro Ueda', Sumiko Nakai, Yasuyoshi Nishida, lack the entire IVS have been found in the gene families of the Hiroshi Hisajima, and Tasuku Honjo* mouse a-globin (Nishioka et al., 1980; Vanin et al., 1980), the lambda chain (Hollis et al., 1982), Department of Genetics, Osaka University Medical School, Osaka 530, human immunoglobulin Japan and the human ,B-tubulin (Wilde et al., 1982a, 1982b). The mouse a-globin processed gene is flanked by long terminal Communicated by K.Rajewsky Received on 30 September 1982 repeats (LTRs) of retrovirus-like intracisternal A particles on both sides, although their orientation is opposite to each There are at least three immunoglobulin epsilon genes (C,1, other (Lueders et al., 1982). The human processed genes CE2, and CE) in the human genome. The nucleotide sequences described above have poly(A)-like tails -20 bases 3' to the of the expressed epsilon gene (CE,) and one (CE) of the two putative poly(A) addition signal and are flanked by direct epsilon pseudogenes were compared. The results show that repeats of several bases on both sides (Hollis et al., 1982; the CE3 gene lacks the three intervening sequences entirely and Wilde et al., 1982a, 1982b). Such direct repeats, which were has a 31-base A-rich sequence 16 bases 3' to the putative also found in human small nuclear RNA pseudogenes poly(A) addition signal, indicating that the CE3 gene is a pro- (Arsdell et al., 1981), might have been formed by repair of cessed gene.
    [Show full text]
  • Young, L.J., & Hammock E.A.D. (2007)
    Update TRENDS in Genetics Vol.23 No.5 Research Focus On switches and knobs, microsatellites and monogamy Larry J. Young1 and Elizabeth A.D. Hammock2 1 Department of Psychiatry and Behavioral Sciences, Center for Behavioral Neuroscience, 954 Gatewood Road, Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA 30322, USA 2 Vanderbilt Kennedy Center and Department of Pharmacology, 465 21st Avenue South, MRBIII, Room 8114, Vanderbilt University, Nashville, TN 37232, USA Comparative studies in voles have suggested that a formation. In male prairie voles, infusion of vasopressin polymorphic microsatellite upstream of the Avpr1a locus facilitates the formation of partner preferences in the contributes to the evolution of monogamy. A recent study absence of mating [7]. The distribution of V1aR in the challenged this hypothesis by reporting that there is no brain differs markedly between the socially monogamous relationship between microsatellite structure and mon- and socially nonmonogamous vole species [8]. Site-specific ogamy in 21 vole species. Although the study demon- pharmacological manipulations and viral-vector-mediated strates that the microsatellite is not a universal genetic gene-transfer experiments in prairie, montane and mea- switch that determines mating strategy, the findings do dow voles suggest that the species differences in Avpr1a not preclude a substantial role for Avpr1a in regulating expression in the brain underlie the species differences in social behaviors associated with monogamy. social bonding among these three closely related species of vole [3,6,9,10]. Single genes and social behavior Microsatellites and monogamy The idea that a single gene can markedly influence Analysis of the Avpr1a loci in the four vole species complex social behaviors has recently received consider- mentioned so far (prairie, montane, meadow and pine voles) able attention [1,2].
    [Show full text]
  • Evaluation of the Effects of Sequence Length and Microsatellite Instability
    Int. J. Biol. Sci. 2019, Vol. 15 2641 Ivyspring International Publisher International Journal of Biological Sciences 2019; 15(12): 2641-2653. doi: 10.7150/ijbs.37152 Research Paper Evaluation of the effects of sequence length and microsatellite instability on single-guide RNA activity and specificity Changzhi Zhao1*, Yunlong Wang2*, Xiongwei Nie1, Xiaosong Han1, Hailong Liu1, Guanglei Li1, Gaojuan Yang1, Jinxue Ruan1, Yunlong Ma1, Xinyun Li1, 3, Huijun Cheng1, Shuhong Zhao1, 3, Yaping Fang2, Shengsong Xie1, 3 1. Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, P. R. China; 2. Agricultural Bioinformatics Key Laboratory of Hubei Province, Hubei Engineering Technology Research Center of Agricultural Big Data, College of Informatics, Huazhong Agricultural University, Wuhan 430070, P. R. China; 3. The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan 430070, P. R. China. *The authors wish it to be known that, in their opinion, the first two authors should be regarded as joint First Authors. Corresponding authors: Shengsong Xie, Tel: 086-027-87387480; Fax: 086-027-87280408; Email: [email protected]; Yaping Fang, Tel: 86-28-87285078; Fax: 86-28-87284285; Email: [email protected]. © The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/). See http://ivyspring.com/terms for full terms and conditions. Received: 2019.07.21; Accepted: 2019.09.02; Published: 2019.10.03 Abstract Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology is effective for genome editing and now widely used in life science research.
    [Show full text]
  • Genome-Wide Mapping and Characterization of Microsatellites In
    www.nature.com/scientificreports OPEN Genome-wide mapping and characterization of microsatellites in the swamp eel genome Received: 14 February 2017 Zhigang Li, Feng Chen, Chunhua Huang, Weixin Zheng, Chunlai Yu, Hanhua Cheng & Accepted: 26 April 2017 Rongjia Zhou Published: xx xx xxxx We described genome-wide screening and characterization of microsatellites in the swamp eel genome. A total of 99,293 microsatellite loci were identified in the genome with an overall density of 179 microsatellites per megabase of genomic sequences. The dinucleotide microsatellites were the most abundant type representing 71% of the total microsatellite loci and the AC-rich motifs were the most recurrent in all repeat types. Microsatellite frequency decreased as numbers of repeat units increased, which was more obvious in long than short microsatellite motifs. Most of microsatellites were located in non-coding regions, whereas only approximately 1% of the microsatellites were detected in coding regions. Trinucleotide repeats were most abundant microsatellites in the coding regions, which represented amino acid repeats in proteins. There was a chromosome-biased distribution of microsatellites in non-coding regions, with the highest density of 203.95/Mb on chromosome 8 and the least on chromosome 7 (164.06/Mb). The most abundant dinucleotides (AC)n was mainly located on chromosome 8. Notably, genomic mapping showed that there was a chromosome-biased association of genomic distributions between microsatellites and transposon elements. Thus, the novel dataset of microsatellites in swamp eel provides a valuable resource for further studies on QTL-based selection breeding, genetic resource conservation and evolutionary genetics. Swamp eel (Monopterus albus) taxonomically belongs to teleosts, the family Synbranchidae of the order Synbranchiformes (Neoteleostei, Teleostei, and Vertebrata).
    [Show full text]
  • Structure of Moloney Murine Leukemia Viral DNA: Nucleotide Sequence Of
    Proc. Nati. Acad. Sci. USA Vol. 77, No. 6, pp. 3307-3311, June 1980 Biochemistry Structure of Moloney murine leukemia viral DNA: Nucleotide sequence of the 5' long terminal repeat and adjacent cellular sequences (strong-stop DNA/recombinant DNA/DNA sequence determination/inverted repeat/transposons) CHARLES VAN BEVEREN*, JANICE G. GODDARD*, ANTON BERNSt, AND INDER M. VERMA* *Tumor Virology Laboratory, The Salk Institute, P.O. Box 85800, San Diego, California 92138; and tLaboratory of Biochemistry, University of Nijmegen, Nijmegen, The Netherlands Communicated by E. Peter Geiduschek, March 31, 1980 ABSTRACT Some unintegrated and all integrated forms tRNAPrO viral DNA contain terminal of murine leukemia long repeats 5' gag pol end @ ib3 (LT s). The entire nucleotide sequence of the LTR and adjacent L-,, i Genomic terminal cellular sequences at the 5' end of a cloned integrated proviral ViralRredundancy DNA obtained from BALB/Mo mouse has been determined. Viral RNA (45-66cbp) It was compared to the nucleotide sequence of the LTR at the Reverse transcription 3' end. The results indicate: (i) a direct 517-nucleotide repeat at yT the 5' and 3' termini; (ii) 145 nucleotides out of 517 nucleotides represent sequences between the 5'-CAP nucleotide and 3' end ent 3' 5 {Cellular DNA of the primer tRNA (strong-stop DNA); (ifi) an li-nucleotide ,-Strong-stop DNA , -Strong-stop DNA inverted repeat is present at the ends of the 5'-LTR and a total (145 bp) of 17 out of21 nucleotides at the termini are inverted repeats; 5'-LTR (145 bp) 3'-LTR-LTR (iv) sequences CAATAAAAG (at positions -24 to -31) and Integrated viral DNA CAATAAAC (at positions +46 to +53) resembling the hypo- thetical DNA-dependent RNA polymerase II promoter site can FIG.
    [Show full text]
  • Repeated Horizontal Transfers of Four DNA Transposons in Invertebrates and Bats Zhou Tang1†, Hua-Hao Zhang2†, Ke Huang3, Xiao-Gu Zhang2, Min-Jin Han1 and Ze Zhang1*
    Tang et al. Mobile DNA (2015) 6:3 DOI 10.1186/s13100-014-0033-1 RESEARCH Open Access Repeated horizontal transfers of four DNA transposons in invertebrates and bats Zhou Tang1†, Hua-Hao Zhang2†, Ke Huang3, Xiao-Gu Zhang2, Min-Jin Han1 and Ze Zhang1* Abstract Background: Horizontal transfer (HT) of transposable elements (TEs) into a new genome is considered as an important force to drive genome variation and biological innovation. However, most of the HT of DNA transposons previously described occurred between closely related species or insects. Results: In this study, we carried out a detailed analysis of four DNA transposons, which were found in the first sequenced twisted-wing parasite, Mengenilla moldrzyki. Through the homology-based strategy, these transposons were also identified in other insects, freshwater planarian, hydrozoans, and bats. The phylogenetic distribution of these transposons was discontinuous, and they showed extremely high sequence identities (>87%) over their entire length in spite of their hosts diverging more than 300 million years ago (Mya). Additionally, phylogenies and comparisons of transposons versus orthologous gene identities demonstrated that these transposons have transferred into their hosts by independent HTs. Conclusions: Here, we provided the first documented example of HT of CACTA transposons, which have been so far extensively studied in plants. Our results demonstrated that bats had continuously acquired new DNA elements via HT. This implies that predation on a large quantity of insects might increase bat exposure to HT. In addition, parasite-host interaction might facilitate exchanging of their genetic materials. Keywords: Horizontal transfer, CACTA transposons, Mammals, Recent activity Background or isolated species.
    [Show full text]
  • Meeting DNA Palindromes Head-To-Head
    Downloaded from genesdev.cshlp.org on September 24, 2021 - Published by Cold Spring Harbor Laboratory Press MEETING REVIEW Meeting DNA palindromes head-to-head Gerald R. Smith1 Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA Particular DNA sequences have long been known to held at Saxtons River, VT, July 6–11, 2008. The struc- have exceptional structures and biological properties. tures discussed included palindromes, Holliday junc- Famous in the medical world are the trinucleotide repeat tions (HJs), G4 DNA, Z DNA, and trinucleotide repeats sequences, such as (CTG)n, and their association with in organisms as diverse as poxvirus, bacteria, yeasts, more than a dozen neurodegenerative diseases. Numer- Drosophila, mice, and humans. One was left with the ous meetings have been held to discuss these repeats and feeling that “standard” (i.e., B-form) linear DNA is inert the diseases they cause. Now, a much-needed meeting relative to the dynamic structures discussed, and that has been held to discuss other noncanonical (non-B-form) these alternative structures deserve their own meeting, DNA structures, their properties, and their biological which, it was agreed, should be continued on a biennial consequences. Although the meeting was titled “DNA basis. palindromes: roles, consequences, and implications of structurally ambivalent DNA,” the participants dis- cussed and debated a range of additional structures— DNA palindromes and inverted repeats—sliding dubbed “Z,” “HJ,” “G4,” and “H” DNA—as well as tri- into cruciforms and hairpins nucleotide repeats. These remarkable structures can have profound effects on chromosomes and organisms, A palindrome, such as the famous “A man, a plan, a ranging from mutational hotspots in bacteria to causes of canal, Panama,” reads the same in both directions.
    [Show full text]
  • Using Rice to Understand the Origin and Amplification Of
    Using rice to understand the origin and amplification of miniature inverted repeat transposable elements (MITEs) Ning Jiang, Ce´ dric Feschotte, Xiaoyu Zhang and Susan R Wessler1 Recent studies of rice miniature inverted repeat transposable Miniature inverted repeat transposable elements (MITEs) elements (MITEs), largely fueled by the availability of genomic are a subset of non-autonomous DNA transposons that sequence, have provided answers to many of the outstanding have a suite of characteristics that distinguish them from questions regarding the existence of active MITEs, their other class 2 non-autonomous elements. MITE families source of transposases (TPases) and their chromosomal have very high copy number (up to several thousand distribution. Although many questions remain about MITE copies), structural homogeneity, and phylogenies that origins and mode of amplification, data accumulated over the are consistent with rapid and extensive amplification of past two years have led to the formulation of testable models. one or a few ‘master’ copies followed by inactivity and drift [2-4,5]. Because MITEs do not encode any TPase Addresses or TPase remnant, their classification has been based on Departments of Plant Biology and Genetics, University of Georgia, shared TIR and target site duplication (TSD) sequences. Athens, Georgia 30602, USA 1 In plants, most MITEs fall into one of two superfamilies; e-mail: [email protected] they are either Tourist-like or Stowaway-like on the basis of their similarity to two elements originally identified in Current Opinion in Plant Biology 2004, 7:115–119 maize and sorghum, respectively [4,6,7]. Both groups are distinguished from all previously described plant trans- This review comes from a themed issue on posons by their having a target sequence preference (i.e.
    [Show full text]
  • Palindrome Resolution and Recombination in the Mammalian Germ Line ERCAN AKGU¨ N,1† JEFFREY ZAHN,1 SUSAN BAUMES,1 GREG BROWN,2 FENG LIANG,1 1 2 1 PETER J
    MOLECULAR AND CELLULAR BIOLOGY, Sept. 1997, p. 5559–5570 Vol. 17, No. 9 0270-7306/97/$04.0010 Copyright © 1997, American Society for Microbiology Palindrome Resolution and Recombination in the Mammalian Germ Line ERCAN AKGU¨ N,1† JEFFREY ZAHN,1 SUSAN BAUMES,1 GREG BROWN,2 FENG LIANG,1 1 2 1 PETER J. ROMANIENKO, SUSANNA LEWIS, * AND MARIA JASIN * Cell Biology and Genetics Program, Sloan-Kettering Institute and Cornell University Graduate School of Medical Sciences, New York, New York 10021,1 and Division of Immunology and Cancer, Hospital for Sick Children Research Institute and Immunology Department, University of Toronto, Toronto, Ontario M5S 1A8, Canada2 Received 21 January 1997/Returned for modification 24 February 1997/Accepted 5 June 1997 Genetic instability is promoted by unusual sequence arrangements and DNA structures. Hairpin DNA structures can form from palindromes and from triplet repeats, and they are also intermediates in V(D)J recombination. We have measured the genetic stability of a large palindrome which has the potential to form a one-stranded hairpin or a two-stranded cruciform structure and have analyzed recombinants at the molec- ular level. A palindrome of 15.3 kb introduced as a transgene was found to be transmitted at a normal Mendelian ratio in mice, in striking contrast to the profound instability of large palindromes in prokaryotic systems. In a significant number of progeny mice, however, the palindromic transgene is rearranged; between 15 and 56% of progeny contain rearrangements. Rearrangements within the palindromic repeat occur both by illegitimate and homologous, reciprocal recombination. Gene conversion within the transgene locus, as quan- titated by a novel sperm fluorescence assay, is also elevated.
    [Show full text]
  • MITE-Based Drives to Transcriptional Control of Genome Host
    bioRxiv preprint doi: https://doi.org/10.1101/108332; this version posted March 4, 2017. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. MITE-based drives to transcriptional control of genome host Luis María Vaschetto1,2 1 Instituto de Diversidad y Ecología Animal, Consejo Nacional de Investigaciones Científicas y Técnicas (IDEA, CONICET), Av. Vélez Sarsfield 299, X5000JJC Córdoba, Argentina 2 Cátedra de Diversidad Animal I, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, (FCEFyN, UNC), Av. Vélez Sarsfield 299, X5000JJC Córdoba, Argentina Abstract In a recent past, Transposable Elements (TEs) were referred as selfish genetic components only capable of copying themselves with the aim to increase the odds that will be inherited. Nonetheless, TEs have been initially proposed as positive control elements acting in synergy with the host. Nowadays, it is well known that TE movement into genome host comprise an important evolutionary mechanism capable to produce diverse chromosome rearrangements and thus increase the adaptive fitness. According to as insights into TE functioning are increasing day to day, the manipulation of transposition has raised an interesting possibility to setting the host functions, although the lack of appropriate genome engineering tools has unpaved it. Fortunately, the emergence of genome editing technologies based on programmable nucleases, and especially the arrival of a multipurpose RNA-guided Cas9 endonuclease system, has made it possible to reconsider this challenge.
    [Show full text]