https://phys.org/news/2022-10-ancient-lineage-microscopic-fungi-upends.html Phys.org Topics * Week's top * Latest news * Unread news * Subscribe [ ] Science X Account [ ] [ ] [*] Remember me Sign In Click here to sign in with or Forget Password? Not a member? Sign up Learn more * Nanotechnology * Physics * Earth * Astronomy & Space * Chemistry * Biology * Other Sciences * Medical Xpress Medicine * Tech Xplore Technology * * share this! * 72 * 16 * Share * Email 1. Home 2. Biology 3. Evolution 1. Home 2. Biology 3. Cell & Microbiology * * * --------------------------------------------------------------------- October 26, 2022 Research into ancient lineage of microscopic fungi upends assumptions about its genetic relationships by Steve Koppes, Purdue University Research into ancient lineage of microscopic fungi upends assumptions about its genetic relationships Rabern Simmons, Purdue's new curator of fungi, named the Clydaea vesicula species of microscopic chytrid fungi after his mother, Clyda Rae Simms, a former teacher in Virginia's Wise County school system, in 2009. A color overlay on the original black-and-white image enhances the specimen's features. Credit: Rabern Simmons. Mycologists tend to base their evolutionary assumptions about all fungi on the higher fungi such as mushrooms, bread molds and yeasts. But that is a mistake, according to a major recent study published in the Proceedings of the National Academy of Sciences. "The traits that the higher fungi possess are not indicative of the lower fungi, the early diverging fungi," said Rabern Simmons, curator of fungi at the Purdue University Herbaria in Botany and Plant Pathology in the College of Agriculture. The evolutionary history of the often-overlooked lineage of chytrid (pronounced kit-trid) fungi has vexed scientists for decades. The study has begun to clarify the complicated details of this lineage, which diverged from the common ancestor that it shares with animals about 750 million to 1 billion years ago. "It takes a lot of our assumptions about early-diverging fungi and the increasing complexity of fungi as you work up the tree and throws them out the window," Simmons said. "We showed that the chytrids still possess a lot of features that link them to that common ancestor. In recent years, certain chytrid fungi have become a scourge of biodiversity. One infamous species of chytrids, described by Simmons' graduate advisor and paper co-author Joyce Longcore at the University of Maine, has caused massive amphibian die-offs and extinctions. Key to the study was how fungi that use different reproductive strategies were related to each other. Haploid organisms reproduce via mitosis cell division and have one set of chromosomes. Diploid organisms have two sets of chromosomes, one from each parent, and most commonly reproduce via meiosis. This produces two haploid gametes, such as sperm and egg in humans, which fuse to form a new diploid organism. Research into ancient lineage of microscopic fungi upends assumptions about its genetic relationships Fimicolochytrium jonesii. A color overlay on the original black-and-white image enhances the specimen's features. Credit: Rabern Simmons. "We started to look at the haploid versus diploid relationships in these fungi as opposed to higher fungi like mushrooms, bread molds and yeasts, things that people more commonly associate when they think of fungi," Simmons said. "We found that a lot of the primary assumptions that haploid gives rise to diploid lifestyle--increasing complexity through the fungal kingdom--were not true. These things were reproducing by mitosis, but they weren't always haploid; some were diploid." Mycologists theorized that the higher fungi began as haploids that eventually gave rise to diploids. "They thought the chytrids probably were much the same. It turns out based on this genomic analysis that that's not the case," Simmons said. [INS::INS] The researchers concluded that fungal evolution proceeded more gradually and with more diversity than previously suspected. Their work led them to agree with some new classifications of chytrid fungi. Biologists classify humans, for example, as belonging to the phylum Chordata (backboned animals), the order of primates (which includes apes and monkeys), and the genus Homo. As recently as the early 2000s, mycologists recognized five orders of chytrid fungi. The PNAS paper confirmed a dramatic reshuffling. "Of those five orders that we understood to be chytrid, three are now their own phylum. And some genera within the remaining two have been pulled out and are now their own phyla. We understand a lot more about what's going on," Simmons said. The paper relies heavily on the University of Michigan's fungi culture collection that Simmons established before coming to Purdue earlier this year. About half of the 1,200 fungi isolates that the Michigan collection comprises came from Joyce Longcore's laboratory at the University of Maine. Research into ancient lineage of microscopic fungi upends assumptions about its genetic relationships Illustrated life cycles observed in fungi. (A) In haplontic life cycles mitosis is limited to the haploid phase, with plasmogamy of gametes followed by meiosis. (B) In diplontic life cycles, mitosis only occurs in the diploid phase with haploid cells only functioning as gametes. (C) Life cycles may alternative between haploid and diploid mitotic phases and may show morphological differences between ploidies as in Allomyces. (D) The dikaryotic life cycle is an alternative to alternation of haploid and diploid generations which lacks diploid mitosis and instead has a phase with two nuclear genotypes undergoing synchronous division. Credit: Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2116841119 The co-authors also included a team of scientists at the U.S. Department of Energy's Joint Genome Institute at the Lawrence Berkeley National Laboratory in California, who generated genome sequences for 69 chytrid fungi. "When Joyce started collecting chytrids, I think she had little idea of just how instrumental a role they would play in resolving some of the big questions in fungal evolution, from the origins of life cycles to abilities to break down plant matter, to helping solve the mystery of the amphibian pandemic," said the University of Michigan's Timothy James, who led the study. "It was a great pleasure working with Rabern, who was a great bridge between the traditional microscopy approaches and the modern genomics methods." Two leading chytrid fungi experts of the 20th century's microscopy era were Purdue's John Karling and the University of Michigan's Frederick Sparrow. The new PNAS paper builds on Karling's and Sparrow's work. "They had some things right and some things wrong," Simmons said. "Hopefully, we can take the best of what they did, the best of what we're doing, and further synthesize that into some excellent mycology that we can pass along to people that don't even think of chytrid fungi when they think of fungi." Longcore commented on how the long-term interplay between Purdue and the University of Michigan regarding chytrid fungi has turned out. "Sparrow and Karling were not close," said Longcore, who worked for Sparrow. "And now Tim James has this great lab at the University of Michigan where Sparrow wrote this big monograph that includes the chytrids. And now Rabern's at Purdue, and I hope he'll have some time to work on chytrids. It's a neat connection between Michigan and Purdue." --------------------------------------------------------------------- Explore further Fungus living inside cave crickets reveals fungal evolution steps --------------------------------------------------------------------- More information: Kevin R. Amses et al, Diploid-dominant life cycles characterize the early evolution of Fungi, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2116841119 Journal information: Proceedings of the National Academy of Sciences Provided by Purdue University Citation: Research into ancient lineage of microscopic fungi upends assumptions about its genetic relationships (2022, October 26) retrieved 30 October 2022 from https://phys.org/news/ 2022-10-ancient-lineage-microscopic-fungi-upends.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. 88 shares * Facebook * Twitter * Email Feedback to editors * Featured * Last Comments * Popular Electrons with Planckian scattering in strange metals follow standard rules of orbital motion in a magnet Oct 28, 2022 0 Synthesizing quantum nanomagnets via metal-free multi-porphyrin systems Oct 28, 2022 0 Whole body 3D images of avian skeletons highlight the role of ecology in evolution Oct 27, 2022 0 A molecular-based, finite-state machine Oct 27, 2022 0 KT Eridani is a recurrent nova, study finds Oct 27, 2022 0 --------------------------------------------------------------------- [gif] Light-analyzing 'lab on a chip' opens door to widespread use of portable spectrometers Oct 29, 2022 [gif] NASA's Lunar Flashlight ready to search for the Moon's water ice Oct 28, 2022 [gif] Artificial intelligence and molecule machine join forces to generalize automated chemistry Oct 28, 2022 [gif] Heat waves driven by climate change have cost global economy trillions since the 1990s Oct 28, 2022 [gif] Researchers design soil-inspired multifunctional chemical system Oct 28, 2022 [gif] Breakthrough in CRISPR research may lead to more effective and safer gene editing Oct 28, 2022 [gif] Safe, sustainable photo-on-demand synthesis of polypeptide precursors Oct 28, 2022 --------------------------------------------------------------------- Relevant PhysicsForums posts Viral spillover risk increases with climate change in High Arctic lake 3 hours ago And Now, here comes COVID-19 version BA.2, BA.4, BA.5, . . . 10 hours ago The impact of the sympathetic nervous system on blood vessels Oct 27, 2022 RSV resurgence out of season Oct 26, 2022 Chornobyl Dark coloured tree frogs Oct 24, 2022 Physics of Blood Pressure and Blood Energy Oct 23, 2022 More from Biology and Medical --------------------------------------------------------------------- * Related Stories [gif] Fungus living inside cave crickets reveals fungal evolution steps Oct 12, 2022 [gif] Phylogenetic analysis reveals the evolution of the mitochondrial calcium transporter Aug 12, 2020 [gif] Weird and wonderful world of fungi shaped by evolutionary bursts, study finds Aug 15, 2022 [gif] Researchers gain insight into the biology of a deadly fungus Feb 08, 2021 [gif] Genome sequences of early-diverging fungi help track origins of white rot fungi May 04, 2016 [gif] Trichaptum mushrooms found to have more than 17,000 gender alleles Apr 21, 2022 * Recommended for you [gif] Social mammals evolve faster than solitary ones, according to new study of evolution Oct 28, 2022 [gif] Identity theft, the secret to a cat parasite's success Oct 28, 2022 [gif] Birds getting smaller, 'wingier' as planet warms, research finds Oct 28, 2022 [gif] A microbe's local environment can be the difference between life and death Oct 28, 2022 [gif] New method uncovers strong effects of copy number variants on the human genome and health Oct 28, 2022 [gif] Revealing the structure of the light-harvesting phycobilisome of cyanobacterium Oct 28, 2022 Load comments (0) Let us know if there is a problem with our content Use this form if you have come across a typo, inaccuracy or would like to send an edit request for the content on this page. For general inquiries, please use our contact form. For general feedback, use the public comments section below (please adhere to guidelines). Please select the most appropriate category to facilitate processing of your request [-- please select one -- ] [ ] [ ] [ ] [ ] [ ] Your message to the editors [ ] Your email (only if you want to be contacted back) [ ] Send Feedback Thank you for taking time to provide your feedback to the editors. Your feedback is important to us. However, we do not guarantee individual replies due to the high volume of messages. E-mail the story Research into ancient lineage of microscopic fungi upends assumptions about its genetic relationships Your friend's email [ ] Your email [ ] [ ] I would like to subscribe to Science X Newsletter. Learn more Your name [ ] Note Your email address is used only to let the recipient know who sent the email. Neither your address nor the recipient's address will be used for any other purpose. The information you enter will appear in your e-mail message and is not retained by Phys.org in any form. [ ] [ ] [ ] [ ] [ ] [ ] [ ] Your message [ ] Send Newsletter sign up Get weekly and/or daily updates delivered to your inbox. You can unsubscribe at any time and we'll never share your details to third parties. [ ] Subscribe More information Privacy policy Medical Xpress Medical Xpress Medical research advances and health news Tech Xplore Tech Xplore The latest engineering, electronics and technology advances Science X Science X The most comprehensive sci-tech news coverage on the web Newsletters [ ] Subscribe Science X Daily and the Weekly Email Newsletter are free features that allow you to receive your favorite sci-tech news updates in your email inbox Follow us * * * * * Top * Home * Search * Mobile version * Help * FAQ * About * Contact * Science X Account * Sponsored Account * Archive * News wire * Android app * iOS app * RSS feeds * Push notification (c) Phys.org 2003 - 2022 powered by Science X Network Privacy policy Terms of use Your Privacy This site uses cookies to assist with navigation, analyse your use of our services, collect data for ads personalisation and provide content from third parties. By using our site, you acknowledge that you have read and understand our Privacy Policy and Terms of Use. Ok Cookie options E-mail newsletter [ ] Subscribe Follow us * * * * It appears that you are currently using Ad Blocking software. What are the consequences? x Quantcast