DOCSLIB.ORG

Karyotype Analysis and Ploidy Determination Using Flow Cytometry in African Bitter Milk Plant “Utazi”, Gongronema Latifolium Benth

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Karyotype Analysis and Ploidy Determination Using Flow Cytometry in African Bitter Milk Plant “Utazi”, Gongronema Latifolium Benth © 2012 The Japan Mendel Society Cytologia 77(1): 43–52 Karyotype Analysis and Ploidy Determination Using Flow Cytometry in African Bitter Milk Plant “Utazi”, Gongronema latifolium Benth Peter O. Aikpokpodion*, Peggy A. Otu and Edak A. Uyoh Department of Genetics and Biotechnology, Faculty of Science, University of Calabar, P.M.B 1115, Calabar, Nigeria Received June 1, 2011; accepted November 28, 2011 Summary Availability of basic genetic information on a plant species is the first pre-requisite in designing any genetic improvement programme for the species. This study was therefore carried out to determine the karyotype of Gongronema latifolium to obtain basic knowledge on ploidy level and karyotype as a first step in understanding the genetics of this spice plant. Karyotype and flow cytom- etry (FCM) studies were carried out on 4 accessions of G. latifolium collected from the humid forest vegetation in Abia, Akwa Ibom, Cross River and Imo States of Nige ria. Chromosome number of Abia accessions were 2n=20 and 22 with karyotype formulae, 3m+4sm+2a+1t and 2m+4sm+ 2a+3t, respectively; Akwa Ibom accessions, 2n=18 with formula: 3m+5sm+1a; Cross River acces- sions, 2n=18 and 22 with formulae: 2m+4sm+2a+1t and 3m+4sm+3a+1t, respectively; Imo acces- sions, 2x=22 and 24 with formulae: 1m+5sm+3a+2t and 2m+7sm+2a+1t, respectively. Results ob- tained revealed cytotype variation and the occurrence of 4 cytotypes, 2n=18, 20, 22 and 24. We therefore conclude that G. latifolium is a diploid species with variable basic numbers. Four basic numbers, n=9, 10, 11 and 12, were therefore proposed for G. latifolium. FCM showed the presence of 2C and 4C DNA content and provided evidence for endoreduplication, a likely evolutionary sur- vival mechanism in this climbing vegetable plant species. This is the first report of karyotype analy- sis in Gongronema latifolium, an important indigenous African vegetable spice plant with huge me- dicinal value. Key words Karyotype, Gongronema latifolium, Endoreduplication, Flow cytomery method, Spice plant, ‘Utazi’. Gongronema latifolium Benth Hook is an important medicinal plant of the family Asclepiadaceae with over 2000 species and some 250 genera widespread in tropical and subtropical regions especially in Africa, southern South America, northern and south eastern Asia with 44 gen- era and 270 species in China (Li et al. 2010). Some well-known tropical ornamental plants such as Orleander, Frangipani, Allamanda, Mandevilla also belong to this family. The sap of most plants in this family is a milky latex containing various alkaloids and glycosides, many of which are used in medicine and as insecticides (Karasov 2001). G. latifolium belongs to a genus of climbers and shrubs of deciduous and secondary forests known to have originated from west Africa and widely distributed in Nigeria, Ghana, Sierra Leone, Guinea Bissau, West Cameroon and other parts of Africa (Burkhill 1985, Okafor 2005, Nwinyi et al. 2008). It is widely dispersed in African forests and farms as wild, semi-wild and cultivated varieties (Odukoya et al. 2007). The leaves are simple and opposite, green to pale green measuring up to 4–8 cm long. Flowers are yellow and dioecious and actinomorphic while follicles are oblong-lanceolate with numerous seeds (about 50–60) strongly compressed with a coma. Ovary is usually superior and fruit is a * Corresponding author, e-mail: [email protected] 44 P. O. Aikpokpodion et al. Cytologia 77(1) drupe, a berry, a capsule or a follicle (Walters and Keil 1996). The stem is soft and pliable and yields characteristic milky exudates when cut (GBIF 2007, Bullock 1961). Gongronema latifolium is popularly identified as ‘Utasi’ by the Efiks, Ibibios and Quas; ‘Utasi’ by the Igbos and ‘Arokeke’ by the Yorubas in Nigeria. It is a highly cherished spice and the parts eaten are the leaves and vines. It imparts a sharp bitter taste and sweet aroma to food, and increases appetite (Adelaja and Fasidi 2009, FAO 1983). The stems are used as chew sticks in Sierra Leone. Extracts or cold infu- sion of pounded leafy branches with lime juice expels intestinal worms, dispels stomach upsets and pains and tones the blood (Agbo et al. 2005). The use of crude leaf extract of this spice in maintain- ing healthy blood glucose levels has been reported (Okafor et al. 1994). Scientific studies have es- tablished the hypoglycemic, hypolipidemic and antioxidant properties of aqueous and ethanolic ex- tracts of G. latifolium leaves (Ugochukwu et al. 2003, Ogundipe et al. 2003). Reports by various authors showed that G. latifolium contains essential oils, saponins and pregnanes among others and has anti-inflammatory properties (Schneider et al. 1993, Morebise and Fafunso 1998, Morebise et al. 2002, Eleyinmi et al. 2008). Abbiw (1990) records that the leaf serves as a vegetable used to prepare ‘pepper soup’ and is eaten raw in any quantity to check excesses of diabetes and hyperten- sion and to treat malaria and typhoid fever. Although of huge medicinal value with great potential for use in pharmaceutical industry, no basic genetic information on G. latifolium has been reported until now. This study was therefore conducted to determine the ploidy level and karyotype of Gongronema latifolium. This information will be invaluable for any subsequent genetic improvement of the crop. Karyotypes describe the number of chromosomes, and what they look like under a light microscope (King et al. 2006). Karyotype studies have been successfully conducted in Dianthus spp. (Jafari and Behroozian 2010); genus Iris (Xiao Fang et al. 2009) and Daucus spp. (Lovene et al. 2008, Xiao Fang et al. 2009). Although karyotype does not look at genes but chromosomes, it provides useful information for an effective plant improvement program. Such information can be used in the characterization of plant agronomic performance, determination of origin and evolution pathway of new species, re- vealing the possible occurrence of genetic disorders and chromosomal abnormalities (Claire 2008). Materials and methods Plant materials G. latifolium accessions used in this study were collected from humid forest vegetation of Abia, Akwa Ibom, Cross River and Imo states of Nigeria (Table 1). Vines of accessions were ob- tained from adult plants and preserved till they were replanted at the Spice Field Genebank located behind the Biological Sciences building University of Calabar (Long. 008°21′E, Lat. 04°47′N 4°56′N, 155 m above sea level). These were planted on on ridges at a spacing of 30 cm between plants and 50 cm between ridges and vines were supported with upright stakes. Weeding and other cultural operations were carried out manually. Karyotype analysis Root tips of Gongronema latifolium were collected between 7:00–11:30 a.m. Immediately Table 1. Collection sites of G. latifolium accessions from humid forest vegetation of Nigeria Village LGA State Latitude °N Longitude °E Altitude (m) Umudike-Uku Ikwuano Abia 04.8604 7.7843 121 Ikot Udobia Etinan Akwa Ibom 04.8863 7.8299 67 Iko-Ekperem Akamkpa Cross River 05.6068 08.2170 10.32 Umuogba Ntu Ngor Okpala Imo 04.9975 08.3330 45.3 2012 Karyotype and Ploidy Level in Gongronema latifolium 45 after harvesting, root tips were pretreated with 8-hydroxyquinoline and kept at room temperature for 3 h. The pretreated root tips and buds were rinsed in distilled water and fixed in a cold mixture of ethanol and acetic acid (3 : 1). Fixed samples were used after 12–24 h or transferred to 70% alco- hol and stored in refrigerator until required. The fixed materi als were hydrolyzed in 1N HCl at 60°C for 5–8 min. Meristematic portions were cut off onto clean slides in a drop of formic lacto propionic (FLP) orcein stain. The meristem was gently tapped with a squashing rod. A cover slip was placed over the top and the excess stain was removed with filter paper by applying a firm thumb pressure. The slides were sealed with nail hardener. Prepared slides were viewed under the microscope at a magnification of ×100. Photographs were taken of chromosomes at the metaphase stage using a Canon Power Shot A630, 8.0 megapixel digital camera with 4× Optical Zoom. The chromosomes were described based on size, arm length, relative length, haploid set length, ratio, number and shape of chromosomes (Vargas et al. 2007, Levan 1964). Measurements of chromosomes were car- ried out using an oculometer (R1370-19) calibrated with a stage micrometer at 0.77 μm for each unit of the oculometer. Ploidy determination by flow cytometry( FCM) Nuclear samples were prepared from intact young vine stem cutting of Gongronema latifolium chopped in a glass Petri dish with new razor blade in 1.0 ml of ice cold nucleic isolation buffer from DNA kit (Cysteine UV, P. Partec GMBH, Germany). The crude suspension was incubated at room temperature for 5 min and then filtered through a 30 μm filter and stained with 4,6-diamidino-2-phe- nyl indole (DAPI). Samples were incubated for 10–15 min period after which they were analyzed in a Partec PA 11 flow cytometer equipped with an air-cooled argon-ion laser (JDS Uniphase, San José, CA, USA) operating at 488 nm. Fluorescence histogram depicting intensity of isolated nuclei was plottedon a semi-logarithmic scale. At least 5,990 nuclei were analysed per sample. For each sample, the percentage of nuclei present in each peak was calculated using the SYSTEM II v.3.0 software (Beckman Coulter, Hialeah, FL, U.S.A.). Ploidy level was determined by comparing the position of dominant peaks corresponding to nuclei at G0–G1 phase of the cell cycle. Results Karyotype analysis The number of somatic chromosomes along with the details of the karyotypes of the studied accessions of Gongronema latifolium is shown in Tables 2 and 3.
Load more

Recommended publications
  • Human Chromosome‐Specific Aneuploidy Is Influenced by DNA
    Article Human chromosome-specific aneuploidy is influenced by DNA-dependent centromeric features Marie Dumont1,†, Riccardo Gamba1,†, Pierre Gestraud1,2,3, Sjoerd Klaasen4, Joseph T Worrall5, Sippe G De Vries6, Vincent Boudreau7, Catalina Salinas-Luypaert1, Paul S Maddox7, Susanne MA Lens6, Geert JPL Kops4 , Sarah E McClelland5, Karen H Miga8 & Daniele Fachinetti1,* Abstract Introduction Intrinsic genomic features of individual chromosomes can contri- Defects during cell division can lead to loss or gain of chromosomes bute to chromosome-specific aneuploidy. Centromeres are key in the daughter cells, a phenomenon called aneuploidy. This alters elements for the maintenance of chromosome segregation fidelity gene copy number and cell homeostasis, leading to genomic instabil- via a specialized chromatin marked by CENP-A wrapped by repeti- ity and pathological conditions including genetic diseases and various tive DNA. These long stretches of repetitive DNA vary in length types of cancers (Gordon et al, 2012; Santaguida & Amon, 2015). among human chromosomes. Using CENP-A genetic inactivation in While it is known that selection is a key process in maintaining aneu- human cells, we directly interrogate if differences in the centro- ploidy in cancer, a preceding mis-segregation event is required. It was mere length reflect the heterogeneity of centromeric DNA-depen- shown that chromosome-specific aneuploidy occurs under conditions dent features and whether this, in turn, affects the genesis of that compromise genome stability, such as treatments with micro- chromosome-specific aneuploidy. Using three distinct approaches, tubule poisons (Caria et al, 1996; Worrall et al, 2018), heterochro- we show that mis-segregation rates vary among different chromo- matin hypomethylation (Fauth & Scherthan, 1998), or following somes under conditions that compromise centromere function.
    [Show full text]
  • Pedigrees and Karyotypes Pedigree
    Pedigrees and Karyotypes Pedigree A pedigree shows the relationships within a family and it helps to chart how one gene can be passed on from generation to generation. Pedigrees are tools used by genetic researchers or counselors to identify a genetic condition running through a family, they aid in making a diagnosis, and aid in determining who in the family is at risk for genetic conditions. On a pedigree: A circle represents a female A square represents a male A horizontal line connecting a male and female represents a marriage A vertical line and a bracket connect the parents to their children A circle/square that is shaded means the person HAS the trait. A circle/square that is not shaded means the person does not have the trait. Children are placed from oldest to youngest. A key is given to explain what the trait is. Marriage Male-DAD Female-MOM Has the trait Male-Son Female-daughter Female-daughter Male- Son Oldest to youngest Steps: ff Ff •Identify all people who have the trait. •For the purpose of this class all traits will be given to you. In other instances, you would have to determine whether or not the trait is autosomal dominant, autosomal recessive, or sex- linked. •In this example, all those who have the trait are homozygous recessive. •Can you correctly identify all genotypes of this family? ff ff Ff Ff •F- Normal •f- cystic fibrosis Key: affected male affected female unaffected male unaffected female Pp Pp PKU P- Unaffected p- phenylketonuria PP or Pp pp Pp pp pp Pp Pp Key: affected male affected female unaffected male unaffected female H-huntington’s hh Hh disease h-Unaffected Hh hh Hh hh Hh hh hh Key: affected male affected female unaffected male unaffected female Sex-Linked Inheritance Colorblindness Cy cc cy Cc Cc cy cy Key: affected male affected female unaffected male unaffected female Karyotypes To analyze chromosomes, cell biologists photograph cells in mitosis, when the chromosomes are fully condensed and easy to see (usually in metaphase).
    [Show full text]
  • The Diversity of Plant Sex Chromosomes Highlighted Through Advances in Genome Sequencing
    G C A T T A C G G C A T genes Review The Diversity of Plant Sex Chromosomes Highlighted through Advances in Genome Sequencing Sarah Carey 1,2 , Qingyi Yu 3,* and Alex Harkess 1,2,* 1 Department of Crop, Soil, and Environmental Sciences, Auburn University, Auburn, AL 36849, USA; [email protected] 2 HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA 3 Texas A&M AgriLife Research, Texas A&M University System, Dallas, TX 75252, USA * Correspondence: [email protected] (Q.Y.); [email protected] (A.H.) Abstract: For centuries, scientists have been intrigued by the origin of dioecy in plants, characterizing sex-specific development, uncovering cytological differences between the sexes, and developing theoretical models. Through the invention and continued improvements in genomic technologies, we have truly begun to unlock the genetic basis of dioecy in many species. Here we broadly review the advances in research on dioecy and sex chromosomes. We start by first discussing the early works that built the foundation for current studies and the advances in genome sequencing that have facilitated more-recent findings. We next discuss the analyses of sex chromosomes and sex-determination genes uncovered by genome sequencing. We synthesize these results to find some patterns are emerging, such as the role of duplications, the involvement of hormones in sex-determination, and support for the two-locus model for the origin of dioecy. Though across systems, there are also many novel insights into how sex chromosomes evolve, including different sex-determining genes and routes to suppressed recombination. We propose the future of research in plant sex chromosomes should involve interdisciplinary approaches, combining cutting-edge technologies with the classics Citation: Carey, S.; Yu, Q.; to unravel the patterns that can be found across the hundreds of independent origins.
    [Show full text]
  • Cytogenetics of Fraxinus Mandshurica and F. Quadrangulata: Ploidy Determination and Rdna Analysis
    Tree Genetics & Genomes (2020) 16:26 https://doi.org/10.1007/s11295-020-1418-6 ORIGINAL ARTICLE Cytogenetics of Fraxinus mandshurica and F. quadrangulata: ploidy determination and rDNA analysis Nurul Islam-Faridi1,2 & Mary E. Mason3 & Jennifer L. Koch4 & C. Dana Nelson5,6 Received: 22 July 2019 /Revised: 1 January 2020 /Accepted: 16 January 2020 # The Author(s) 2020 Abstract Ashes (Fraxinus spp.) are important hardwood tree species in rural, suburban, and urban forests of the eastern USA. Unfortunately, emerald ash borer (EAB, Agrilus planipennis) an invasive insect pest that was accidentally imported from Asia in the late 1980s–early 1990s is destroying them at an alarming rate. All North American ashes are highly susceptible to EAB, although blue ash (F. quadrangulata) may have some inherent attributes that provide it some protection. In contrast Manchurian ash (F. mandshurica) is relatively resistant to EAB having coevolved with the insect pest in its native range in Asia. Given its level of resistance, Manchurian ash has been considered for use in interspecies breeding programs designed to transfer resistance to susceptible North American ash species. One prerequisite for successful interspecies breeding is consistency in chromosome ploidy level and number between the candidate species. In the current study, we cytologically determined that both Manchurian ash and blue ash are diploids (2n) and have the same number of chromosomes (2n =2x = 46). We also characterized these species’ ribosomal gene families (45S and 5S rDNA) using fluorescence in situ hybridization (FISH). Both Manchurian and blue ash showed two 45S rDNA and one 5S rDNA sites, but blue ash appears to have an additional site of 45S rDNA.
    [Show full text]
  • The Longest Telomeres: a General Signature of Adult Stem Cell Compartments
    Downloaded from genesdev.cshlp.org on September 25, 2021 - Published by Cold Spring Harbor Laboratory Press The longest telomeres: a general signature of adult stem cell compartments Ignacio Flores,1 Andres Canela,1 Elsa Vera,1 Agueda Tejera,1 George Cotsarelis,2 and María A. Blasco1,3 1Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid E-28029, Spain; 2University of Pennsylvania School of Medicine, M8 Stellar-Chance Laboratories, Philadelphia, Pennsylvania 19104, USA Identification of adult stem cells and their location (niches) is of great relevance for regenerative medicine. However, stem cell niches are still poorly defined in most adult tissues. Here, we show that the longest telomeres are a general feature of adult stem cell compartments. Using confocal telomere quantitative fluorescence in situ hybridization (telomapping), we find gradients of telomere length within tissues, with the longest telomeres mapping to the known stem cell compartments. In mouse hair follicles, we show that cells with the longest telomeres map to the known stem cell compartments, colocalize with stem cell markers, and behave as stem cells upon treatment with mitogenic stimuli. Using K15-EGFP reporter mice, which mark hair follicle stem cells, we show that GFP-positive cells have the longest telomeres. The stem cell compartments in small intestine, testis, cornea, and brain of the mouse are also enriched in cells with the longest telomeres. This constitutes the description of a novel general property of adult stem cell compartments. Finally, we make the novel finding that telomeres shorten with age in different mouse stem cell compartments, which parallels a decline in stem cell functionality, suggesting that telomere loss may contribute to stem cell dysfunction with age.
    [Show full text]
  • Arabidopsis MZT1 Homologs GIP1 and GIP2 Are Essential for Centromere Architecture
    Arabidopsis MZT1 homologs GIP1 and GIP2 are essential for centromere architecture Morgane Batzenschlagera, Inna Lermontovab, Veit Schubertb, Jörg Fuchsb, Alexandre Berra, Maria A. Koinic, Guy Houlnéa, Etienne Herzoga, Twan Ruttenb, Abdelmalek Aliouaa, Paul Franszc, Anne-Catherine Schmita, and Marie-Edith Chaboutéa,1 aInstitut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 67000 Strasbourg, France; bLeibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Stadt Seeland, Germany; and cSwammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH, Amsterdam, The Netherlands Edited by James A. Birchler, University of Missouri, Columbia, MO, and approved May 12, 2015 (received for review April 2, 2015) Centromeres play a pivotal role in maintaining genome integrity Previously, we characterized the γ-tubulin complex protein 3- by facilitating the recruitment of kinetochore and sister-chromatid interacting proteins (GIPs), GIP1 and GIP2 (Table S1), as es- cohesion proteins, both required for correct chromosome segre- sential for the recruitment of γ-tubulin complexes at microtubule gation. Centromeres are epigenetically specified by the presence (MT) organizing centers in Arabidopsis (7, 8). This function seems of the histone H3 variant (CENH3). In this study, we investigate the conservedinthehumanandSchizosaccharomyces pombe GIP role of the highly conserved γ-tubulin complex protein 3-interact- homologs named mitotic spindle organizing protein 1 (MZT1) ing proteins (GIPs) in Arabidopsis centromere regulation. We show (9–11). More recently, we localized GIPs at the nucleoplasm pe- that GIPs form a complex with CENH3 in cycling cells. GIP depletion riphery, close to chromocenters, where they modulate the nuclear in the gip1gip2 knockdown mutant leads to a decreased CENH3 architecture (12, 13).
    [Show full text]
  • Cytogenetics, Chromosomal Genetics
    Cytogenetics Chromosomal Genetics Sophie Dahoun Service de Génétique Médicale, HUG Geneva, Switzerland [email protected] Training Course in Sexual and Reproductive Health Research Geneva 2010 Cytogenetics is the branch of genetics that correlates the structure, number, and behaviour of chromosomes with heredity and diseases Conventional cytogenetics Molecular cytogenetics Molecular Biology I. Karyotype Definition Chromosomal Banding Resolution limits Nomenclature The metaphasic chromosome telomeres p arm q arm G-banded Human Karyotype Tjio & Levan 1956 Karyotype: The characterization of the chromosomal complement of an individual's cell, including number, form, and size of the chromosomes. A photomicrograph of chromosomes arranged according to a standard classification. A chromosome banding pattern is comprised of alternating light and dark stripes, or bands, that appear along its length after being stained with a dye. A unique banding pattern is used to identify each chromosome Chromosome banding techniques and staining Giemsa has become the most commonly used stain in cytogenetic analysis. Most G-banding techniques require pretreating the chromosomes with a proteolytic enzyme such as trypsin. G- banding preferentially stains the regions of DNA that are rich in adenine and thymine. R-banding involves pretreating cells with a hot salt solution that denatures DNA that is rich in adenine and thymine. The chromosomes are then stained with Giemsa. C-banding stains areas of heterochromatin, which are tightly packed and contain
    [Show full text]
  • Mitosis Meiosis Karyotype
    POGIL Cell Biology Activity 7 – Meiosis/Gametogenesis Schivell MODEL 1: karyotype Meiosis Mitosis 1 POGIL Cell Biology Activity 7 – Meiosis/Gametogenesis Schivell MODEL 2, Part 1: Spermatogenesis The trapezoid below represents a small portion of the wall of a "seminiferous tubule" within the testis. The cells in each of the panels are all originally derived from the single cell in panel 1. 1 2 3 Outside of tubule Lumen of tubule 4 5 6 7 8 9 2 POGIL Cell Biology Activity 7 – Meiosis/Gametogenesis Schivell MODEL 2, Part 2: vas epididymis deferens testis (plural: testes) seminiferous tubules (cut) Courtesy of: Dr. E. Kent Christensen, U. of Michigan lumen of seminiferous tubule sperm This portion shown expanded in part 1 of Model 2 3 POGIL Cell Biology Activity 7 – Meiosis/Gametogenesis Schivell MODEL 3: Oogenesis This is a time lapse of an ovary showing one "follicle" as it develops from immaturity to ovulation. The follicle starts in panel 1 as a small sphere of "follicle cells" surrounding the oocyte. In each panel, chromosomes within the oocyte are shown as an inset. (There are actually thousands of follicles in each mammalian ovary). 1 2 3 4 5 6 7 4 POGIL Cell Biology Activity 7 – Meiosis/Gametogenesis Schivell Model 1 questions: 1. Using the same type of cartoon as model 1, draw an "unreplicated", condensed chromosome. 2. Draw a replicated, condensed chromosome: 3. Circle a homologous pair in the karyotype. Remember that one of these chromosomes came from the male parent and the other from the female parent. These two chromosomes carry the same genes! (But can have different alleles on each homolog.) 4.
    [Show full text]
  • Comprehensive Chromosomal and Mitochondrial Copy Number Profiling in Human IVF Embryos
    ARTICLE IN PRESS 1bs_bs_query Q2 Article 2bs_bs_query 3bs_bs_query Comprehensive chromosomal and mitochondrial copy 4bs_bs_query 5bs_bs_query number profiling in human IVF embryos 6bs_bs_query Q1 a,1, a,1 a a 7bs_bs_query Wei Shang *, Yunshan Zhang , Mingming Shu , Weizhou Wang , a a b b, b b 8bs_bs_query Likun Ren , Fu Chen , Lin Shao , Sijia Lu *, Shiping Bo , Shujie Ma , b 9bs_bs_query Yumei Gao a 10bs_bs_query Assisted Reproductive Centre of the Department of Gynaecology and Obstetrics, PLA Naval General Hospital, 11 bs_bs_query Haidian District, Beijing 100048, China b 12bs_bs_query Yikon Genomics, Fengxian District, Shanghai 201400, China 13bs_bs_query 14bs_bs_query 15bs_bs_query Wei Shang has been the Associate Chief Physician at the Department of Gynaecology and Obstetrics, PLA Naval 16bs_bs_query General Hospital, Beijing, since 2005. Her research interests focus on assisted reproduction technology, repro- 17bs_bs_query ductive endocrinology and ovary dysfunction. 18bs_bs_query 19bs_bs_query KEY MESSAGE 20bs_bs_query Using a validated approach called MALBAC-NGS, a comprehensive chromosomal and mitochondrial copy number 21bs_bs_query profiling in human embryos was conducted, and correlations of mitochondria quantity with maternal age and 22bs_bs_query embryo stage were observed. The strategy might be used to perform an advanced PGS targeting both chro- 23bs_bs_query mosomal and mitochondria copy numbers. 24bs_bs_query 25bs_bs_query ABSTRACT 26bs_bs_query 27bs_bs_query Single cell whole genome sequencing helps to decipher the genome
    [Show full text]
  • Proctor Booklet
    3.11 C: Meiosis Quiz PROCTOR VERSION 1. Which diagram best illustrates the processes of DNA replication, meiosis, and separation of sister chromatids? (A) Distractor Rationale: This answer suggests the student may understand that meiosis involves the splitting of homologous chromosomes, but does not understand that the first step in this process is the replication of all chromosomes to create a pair of two chromatids attached by a centromere (the X-shaped structures), and that the last step is the separation of sister chromatids in meiosis II to create four daughter cells, each containing a long chromosome and a short chromosome. (B) Distractor Rationale: This answer suggests the student may understand that meiosis involves the replication of all chromosomes and the pairing up and separation of homologous chromosomes, but does not understand that the final step in this process is the separation of sister chromatids in meiosis II to produce four haploid daughter cells, each with the haploid number of chromosomes. (C) Page 1 of 8 3.11 C: Meiosis Quiz PROCTOR VERSION Distractor Rationale: This answer suggests the student may understand that meiosis involves the replication of all chromosomes and the separation of sister chromatids, but does not realize that the first division involves the pairing up and separation of homologous chromosomes, and that this is then followed by a second division that produces four daughter cells, each with the haploid number of chromosomes. (D) Rationale: This answer suggests the student understands that the representation accurately depicts how the process of meiosis produces four haploid cells from one diploid parent cell: the formation of chromosomes, formation of the spindle complex, pairing of homologs, lining up of homologs on the equator, migration of chromosomes, and two divisions.
    [Show full text]
  • DNA Ploidy Cell Cycle Analysis AHS – M2136
    Corporate Medical Policy DNA Ploidy Cell Cycle Analysis AHS – M2136 File Name: dna _ploidy_cell_cycle_analysis Origination: 1/2019 Last CAP Review: 3/2021 Next CAP Review: 3/2022 Last Review: 7/2021 Description of Procedure or Service S-phase fraction (SPF) is an assessment of how many cells a re a ctively synthesizing DNA (UIHC, 2016). It is used as a measure of cell proliferation, particularly for cancer (Pinto, André, & Soares, 1999). ***Note: This Medical Policy is complex and technical. For questions concerning the technical language and/or specific clinical indications for its use, please consult your physician. Policy DNA ploidy cell cycle analysis is not covered. BCBSNC will not reimburse for non-covered services or procedures. Benefits Application This medical policy relates only to the services or supplies described herein. Please refer to the Member's Benefit Booklet for availability of benefits. Member's benefits may vary according to benefit design; therefore member benefit language should be reviewed before applying the terms of this medical policy. When DNA Ploidy Cell Cycle Analysis is covered Not Applicable. When DNA Ploidy Cell Cycle Analysis is not covered Reimbursement is not allowed for the measurement of flow cytometry-derived DNA content (DNA index) or cell prolifera tive a ctivity (S-phase fraction or % S-phase) for prognostic or therapeutic purposes in the routine clinical management of cancers. Policy Guidelines Cancer is the uncontrolled growth and spread of abnormal cells and is increasingly shown to be initiated, propagated, and maintained by somatic genetic events (Johnson et al., 2014). In 2020, an expected 1,806,590 Americans will be diagnosed with new cancer cases and 606,520 Americans will die from the disease (Siegel, Miller, & Jema l, 2020).
    [Show full text]
  • Flow Cytometry-Based Determination of Ploidy from Dried Leaf Specimens in Genomically Complex Collections of the Tropical Forage Grass Urochloa S
    G C A T T A C G G C A T genes Article Flow Cytometry-Based Determination of Ploidy from Dried Leaf Specimens in Genomically Complex Collections of the Tropical Forage Grass Urochloa s. l. Paulina Tomaszewska 1,* , Till K. Pellny 2, Luis M. Hernández 3, Rowan A. C. Mitchell 2, Valheria Castiblanco 3, José J. de Vega 4, Trude Schwarzacher 1 and Pat (J.S.) Heslop-Harrison 1 1 Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester LE1 7RH, UK; [email protected] (T.S.); [email protected] (P.H.-H.) 2 Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK; [email protected] (T.K.P.); [email protected] (R.A.C.M.) 3 International Center for Tropical Agriculture (CIAT), Cali 6713, Colombia; [email protected] (L.M.H.); [email protected] (V.C.) 4 Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK; [email protected] * Correspondence: [email protected] Abstract: Urochloa (including Brachiaria, Megathyrus and some Panicum) tropical grasses are native to Africa and are now, after selection and breeding, planted worldwide, particularly in South America, Citation: Tomaszewska, P.; Pellny, as important forages with huge potential for further sustainable improvement and conservation of T.K.; Hernández, L.M.; Mitchell, grasslands. We aimed to develop an optimized approach to determine ploidy of germplasm collection R.A.C.; Castiblanco, V.; de Vega, J.J.; of this tropical forage grass group using dried leaf material, including approaches to collect, dry Schwarzacher, T.; Heslop-Harrison, P.
    [Show full text]