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FUNGI POSTER CHILD. “The paradigmatic example is S. cerevisiae in which a relatively small region of the genome, less than a thousand base pairs, expresses in the alternate mating types one or two key cell fate determinants, all of which are transcription factors responsible for orchestrating both haploid cell type specificity (a or α) and the diploid zygote fate (a/α).” https://lnkd.in/dn4azG7 View in LinkedIn

LARGE KINGDOM. “There are an estimated 5 million species of fungi, and maybe more, much remains to be learned about their sexual nature. Many fungi are currently classified as asexual, and yet many fungi long thought to be asexual have been subsequently found to be sexual, or in some cases at least parasexual (i.e. C. albicans).” https://lnkd.in/dn4azG7 View in LinkedIn

THE DIVERSE KINGDOM. “What about fungi? Relatively few fungi have large size dimorphic sex chromosomes, but there are a few well studied examples such as Neurospora tetrasperma, Podospora, and Microbotryum. Most fungi have relatively smaller regions of their genome, called mating-type loci, or MAT for short, that dictate their mating type.” https://lnkd.in/dn4azG7 View in LinkedIn

A little princess. View in LinkedIn

NO SINGLE WAY. “To summarize, in simple terms the ways in which sex is determined are plastic and diverse.” https://lnkd.in/dn4azG7 View in LinkedIn

SO ENDS this second weekend on a fungal perspective of why sexual reproduction arose during evolution. Few kingdoms are as sexually diverse and plastic as fungi, and they serve as an extreme reference point for the relatively less plastic reproduction of animals and plants. Regardless, living creatures have devised an enormous varieties of methods to create viable progeny and perpetuate that all-important germline into the future, while limiting inbreeding and creating useful genes for adaptation while purging deleterious genes. No small task. View in LinkedIn

QUANTITATIVE TRIGGER. “Finally in some lines of the zebra fish Danio rerio sex appears to be a quantitative trait, in which genes on multiple different chromosomes come together in allelic combinations that favor either female or male fate. This quantitative sex determining system has been termed polygenic sex determination (PSD).” https://lnkd.in/dn4azG7 View in LinkedIn

THE SECOND DIVIDING LINE. “Taken from the perspective of diverse and plastic sex chromosomes and mating-type loci from at least 5 of the 8 supergroups of the eukaryotes, there seems to be nothing ancestral or static about sex determination.” https://lnkd.in/dn4azG7 View in LinkedIn

TEMPERATURE + STRUCTURE TRIGGERS. “Yet other species appear to be hybrids of the two with features of both environmental and chromosomal sex determination.” https://lnkd.in/dn4azG7 View in LinkedIn

ONE DIVIDING LINE. “Phylogenetic reconstructions across the fungal kingdom support the conclusion that bipolar mating type is an ancestral state and the tetrapolar configuration is a derived state.” https://lnkd.in/dn4azG7 View in LinkedIn