Plant Breeding Department, Institute for Sustainable Agriculture, Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC), Avenida Menéndez Pidal S/N., Campus Alameda del Obispo, 14004, Córdoba, Spain.
Área de Fisiología Vegetal, Universidad de Córdoba, Campus de Rabanales, Edif. C4, 3ª Planta, Córdoba, Spain.
Sci Rep. 2022 Jun 22;12(1):10597. doi: 10.1038/s41598-022-14843-1.
The increasing human population demands an increase in crop yields that must be implemented through breeding programmes to ensure a more efficient and sustainable production of agro-food products. In the framework of breeding, genetic crosses are developed between cultivated species such as wheat and their relative species that are used as genetic donors to transfer desirable agronomic traits into the crop. Unfortunately, interspecific associations between chromosomes from the donor species and the cultivar are rare during meiosis, the process to produce gametes in organisms with sexual reproduction, hampering the transfer of genetic variability into wheat. In addition, little is known about how homologous (equivalent) chromosomes initiate interaction and recognition within the cell nucleus to enter meiosis. In this context, we aim to get insight into wheat chromatin structure, particularly the distribution of homologous chromosomes within the cell nucleus and their putative interactions in premeiotic stages to facilitate chromosome associations and recombination at the beginning of meiosis. Cytogenetics allows the study of both the structure and the behaviour of chromosomes during meiosis and is key in plant breeding. In this study we visualized an extra pair of barley homologous chromosomes in a wheat genetic background to study the spatial distribution, arrangements and interactions occurring exclusively between this pair of homologous chromosomes during premeiosis using fluorescence in situ hybridization (FISH). Our results suggest that homologous chromosomes can initiate interactions in premeiotic stages that could facilitate the processes of specific chromosome recognition and association occurring at the onset of meiosis.
人口的增长要求增加作物产量，这必须通过育种计划来实现，以确保农业食品产品的生产更高效、更可持续。在育种框架内，在小麦等栽培物种与其作为遗传供体的相关物种之间开发遗传杂交，以将理想的农艺性状转移到作物中。不幸的是，在有性繁殖生物中产生配子的减数分裂过程中，供体物种和栽培种之间的种间染色体联系很少，这阻碍了遗传变异向小麦的转移。此外，对于同源（等效）染色体如何在细胞核内启动相互作用和识别以进入减数分裂，人们知之甚少。在这方面，我们旨在深入了解小麦染色质结构，特别是同源染色体在细胞核内的分布及其在减数分裂前期阶段的潜在相互作用，以促进减数分裂开始时的染色体关联和重组。细胞遗传学允许研究减数分裂过程中染色体的结构和行为，是植物育种的关键。在这项研究中，我们在小麦遗传背景下可视化了一对额外的大麦同源染色体，以使用荧光原位杂交（FISH）研究减数分裂前期这对同源染色体之间发生的空间分布、排列和相互作用。我们的结果表明，同源染色体可以在减数分裂前期启动相互作用，这可能有助于减数分裂开始时发生的特定染色体识别和关联过程。
