Natural Variation and Genetic Determinants of Caenorhabditis elegans Sperm Size
Natural Variation and Genetic Determinants of Caenorhabditis elegans Sperm Size
复制标题
DOI：
10.1534/genetics.119.302462
复制
发表时间：
2019-10-01
期刊：
影响因子：
3.3
通讯作者：
Braendle, Christian
中科院分区：
文献类型：
--
作者：
Gimond, Clotilde;Vielle, Anne;Braendle, Christian
精子形状和大小的多样性代表了理解选择如何驱动细胞形态进化多样化的强大范例。对雄性两性线虫秀丽隐杆线虫（Caelophabditis elegans）精子生物学的实验研究阐明了精子受精成功的多种重要因素，包括较大精子的竞争优势。然而，尽管有广泛的研究，调节C。秀丽线虫精子的大小和精子大小自然变异的遗传基础仍然未知。为了解决这些问题，我们量化了全球97个遗传上不同的C。elegans菌株，使我们能够发现男性精子大小的显着遗传变异。目的研究C.线虫雄性精子大小变异的全基因组关联研究中，我们没有发现任何显着的数量性状位点。因此，我们专注于最近分离的实验室菌株（N2与LSJ 1/2）之间观察到的显著精子大小差异的遗传分析。使用突变体和定量互补试验，我们证明了基因nurf-1的变异是LSJ谱系中小精子进化的基础。鉴于先前的发现，这种相同的nurf-1变异是雌雄同体实验室适应的核心，LSJ品系中雄性精子大小减少的进化可能反映了多效性的结果。总之，我们的研究结果提供了一个全面的量化自然变化的C。elegans精子大小和小杆线虫精子大小的遗传决定因素的第一个见解，指出参与了cDNAF染色质重塑复合物。
The diversity in sperm shape and size represents a powerful paradigm to understand how selection drives the evolutionary diversification of cell morphology. Experimental work on the sperm biology of the male-hermaphrodite nematode Caenorhabditis elegans has elucidated diverse factors important for sperm fertilization success, including the competitive superiority of larger sperm. Yet despite extensive research, the molecular mechanisms regulating C. elegans sperm size and the genetic basis underlying natural variation in sperm size remain unknown. To address these questions, we quantified male sperm size variation of a worldwide panel of 97 genetically distinct C. elegans strains, allowing us to uncover significant genetic variation in male sperm size. Aiming to characterize the molecular genetic basis of C. elegans male sperm size variation using a genome-wide association study, we did not detect any significant quantitative trait loci. We therefore focused on the genetic analysis of pronounced sperm size differences observed between recently diverged laboratory strains (N2 vs. LSJ1/2). Using mutants and quantitative complementation tests, we demonstrate that variation in the gene nurf-1 underlies the evolution of small sperm in the LSJ lineage. Given the previous discovery that this same nurf-1 variation was central for hermaphrodite laboratory adaptation, the evolution of reduced male sperm size in LSJ strains likely reflects a pleiotropic consequence. Together, our results provide a comprehensive quantification of natural variation in C. elegans sperm size and first insights into the genetic determinants of Caenorhabditis sperm size, pointing at an involvement of the NURF chromatin remodeling complex.