{"title":"Dosage Effect of the Ph1 Locus on Homologous Crossovers in a Segment of Chromosome 1B of Bread Wheat (Triticum aestivum L.).","authors":"Adam J Lukaszewski","doi":"10.1159/000541484","DOIUrl":null,"url":null,"abstract":"<p><strong>Introduction: </strong>The Ph1 locus in polyploid wheat enforces strictly bivalent behaviour in meiotic metaphase I, by preventing homoeologues from crossing over. It has always been considered as completely dominant as no homoeologous metaphase I pairing has ever been detected with its single dose present. However, Ph1 also affects pairing and crossing over of homologous chromosomes.</p><p><strong>Methods: </strong>Homologous crossover frequencies with Ph1 in two, one, and null doses were scored cytologically, as exchanges within a ca. 9.5-9.9 Mbp terminal wheat segment of a wheat-rye translocation T-9 and corresponding segments in chromosome arms 1BS originating from four wheat cultivars.</p><p><strong>Results: </strong>In all cases, the crossover rates in the tested homologous segment of wheat genome, with a single dose of Ph1 present, were intermediate between those at two and null Ph1 doses. Averaging across all four chromosomes, the crossover rate with a single dose of Ph1 present was 37% higher from that with two doses and 46.4% lower of that with a zero dosage.</p><p><strong>Conclusion: </strong>The Ph1 locus in wheat affects homologues and appears to operate in a dosage-dependent manner.</p>","PeriodicalId":11206,"journal":{"name":"Cytogenetic and Genome Research","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cytogenetic and Genome Research","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1159/000541484","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Introduction: The Ph1 locus in polyploid wheat enforces strictly bivalent behaviour in meiotic metaphase I, by preventing homoeologues from crossing over. It has always been considered as completely dominant as no homoeologous metaphase I pairing has ever been detected with its single dose present. However, Ph1 also affects pairing and crossing over of homologous chromosomes.
Methods: Homologous crossover frequencies with Ph1 in two, one, and null doses were scored cytologically, as exchanges within a ca. 9.5-9.9 Mbp terminal wheat segment of a wheat-rye translocation T-9 and corresponding segments in chromosome arms 1BS originating from four wheat cultivars.
Results: In all cases, the crossover rates in the tested homologous segment of wheat genome, with a single dose of Ph1 present, were intermediate between those at two and null Ph1 doses. Averaging across all four chromosomes, the crossover rate with a single dose of Ph1 present was 37% higher from that with two doses and 46.4% lower of that with a zero dosage.
Conclusion: The Ph1 locus in wheat affects homologues and appears to operate in a dosage-dependent manner.
期刊介绍:
During the last decades, ''Cytogenetic and Genome Research'' has been the leading forum for original reports and reviews in human and animal cytogenetics, including molecular, clinical and comparative cytogenetics. In recent years, most of its papers have centered on genome research, including gene cloning and sequencing, gene mapping, gene regulation and expression, cancer genetics, comparative genetics, gene linkage and related areas. The journal also publishes key papers on chromosome aberrations in somatic, meiotic and malignant cells. Its scope has expanded to include studies on invertebrate and plant cytogenetics and genomics. Also featured are the vast majority of the reports of the International Workshops on Human Chromosome Mapping, the reports of international human and animal chromosome nomenclature committees, and proceedings of the American and European cytogenetic conferences and other events. In addition to regular issues, the journal has been publishing since 2002 a series of topical issues on a broad variety of themes from cytogenetic and genome research.