biostudies-literatureMa YCAS | Bureau of Frontier Sciences and Education, Chinese Academy of Sciences (BFSE)MOST | National Natural Science Foundation of China (NSFC)China Postdoctoral Science FoundationCAS | Bureau of Frontier Sciences and Education, Chinese Academy of SciencesMOST | National Natural Science Foundation of ChinaChina Postdoctoral Science Foundation (China Postdoctoral Foundation Project)e2315531121https://www.ebi.ac.uk/biostudies/studies/S-EPMC10990102biostudies-literatureUnknown121(13)Mating type (sex) plays a crucial role in regulating sexual reproduction in most extant eukaryotes. One of the functions of mating types is ensuring self-incompatibility to some extent, thereby promoting genetic diversity. However, heterothallic mating is not always the best mating strategy. For example, in low-density populations or specific environments, such as parasitic ones, species may need to increase the ratio of potential mating partners. Consequently, many species allow homothallic selfing (i.e., self-fertility or intraclonal mating). Throughout the extensive evolutionary history of species, changes in environmental conditions have influenced mating strategies back and forth. However, the mechanisms through which mating-type recognition regulates sexual reproduction and the dynamProceedings of the National Academy of Sciences of the United States of AmericaCip1, a CDK regulator, determines heterothallic mating or homothallic selfing in a protist.PMC10990102322003442021M70343332130011ZDBS-LY-SM026Xiong JZhang JMa YMiao WYan GfalseCip1, a CDK regulator, determines heterothallic mating or homothallic selfing in a protist.Mating type (sex) plays a crucial role in regulating sexual reproduction in most extant eukaryotes. One of the functions of mating types is ensuring self-incompatibility to some extent, thereby promoting genetic diversity. However, heterothallic mating is not always the best mating strategy. For example, in low-density populations or specific environments, such as parasitic ones, species may need to increase the ratio of potential mating partners. Consequently, many species allow homothallic selfing (i.e., self-fertility or intraclonal mating). Throughout the extensive evolutionary history of species, changes in environmental conditions have influenced mating strategies back and forth. However, the mechanisms through which mating-type recognition regulates sexual reproduction and the dynam2024-01-01T00:00:00Z2024 Mar2025-04-22T14:08:52.449Z2025-04-06T00:54:03.857ZS-EPMC109901023849870410.1073/pnas.2315531121