The fastest-evolving genes in eukaryotes commonly encode reproductive proteins—and the rate at which genes for male reproductive proteins change, in particular, often vastly outstrips the rate of change across the genome as a whole.
A recent paper in G3: Genes|Genomes|Genetics describes an unusual exception: the amino acid sequences of the most abundant sperm proteins in many nematodes are almost completely static. Authors Katja Kasimatis and Patrick Phillips found that the amino acid sequences of these major sperm proteins (MSPs) are some of the most conserved of any known protein in any organism; their glacial rate of change is on par with that of essential proteins like the histones that act as spools for genomic DNA.
Despite defying the expectation that sperm proteins should evolve rapidly due to sperm competition and coevolution with egg proteins, the sluggish rate of MSP sequence change can be explained. Like many sperm proteins, MSPs are pleiotropic—that is, they have more than one job, and these functions are sometimes seemingly unrelated. In addition to being essential for sperm movement, MSPs act as signaling molecules in eggs, meaning that any sequence changes that improve sperm motility could also affect egg function, and not necessarily in a positive way.
MSPs may be frozen by pleiotropy at the sequence level, but it wouldn’t be accurate to say they’re not evolving. Taking a zoomed-out view of the whole genomes of several nematode species, Kasimatis and Phillips saw that genes for MSPs aren’t fixed at all: over evolutionary time, they have changed dramatically in copy number and have even jumped from chromosome to chromosome. Variations like these can have functional relevance, since copy number changes can alter the amount of protein produced from a gene, and changing the location of a gene within the genome can alter its regulation.
This peculiar example shows how reproductive proteins are driven to evolve rapidly, even when their sequences are constrained to an extreme degree—and demonstrates how a broader view of entire genomes and gene family dynamics is sometimes critical for understanding a gene’s evolutionary history.
CITATION:
Kasimatis, K.; Phillips, P. Rapid Gene Family Evolution of a Nematode Sperm Protein Despite Sequence Hyper-conservation.
G3, 8(1), 353-362.
DOI: 10.1534/g3.117.300281
http://www.g3journal.org/content/8/1/353
Nicole Haloupek is a freelance science writer and a recent graduate of UC Berkeley's molecular and cell biology PhD program.
View all posts by Nicole Haloupek »Read more in
-
Hongyu Zhao joins GENETICS as new Senior Editor
A new senior editor is joining GENETICS in the Statistical Genetics and Genomics section. We’re excited to welcome Hongyu Zhao to the editorial team. Hongyu ZhaoSenior Editor Hongyu Zhao is the Ira V. Hiscock Professor of Biostatistics, Professor of Genetics, and Professor of Statistics and Data Science at Yale University. He received his BS in…
-
GSA Member Julio Molina Pineda Receives DeLill Nasser Award, Shines at TAGC 2024
“At any career stage, the GSA membership is an amazing investment for any genetics professional!” Julio Molina Pineda is a PhD Candidate in Cell and Molecular Biology and a Research Assistant at the University of Arkansas, and a Doctoral Academy Fellow at the Lewis Lab. In 2023, Julio was awarded the DeLill Nasser Award for…
-
In Memoriam: Ellsworth Herman Grell (1932–2023), a pioneer of Drosophila genome engineering and annotation
Ellsworth (Ed) Grell blessed the Drosophila community through three enduring legacies: as a pioneer of chromosome mechanics, as a primary organizer and synthesizer of genetic knowledge in Drosophila, and as a graceful mentor to those fortunate to have known him personally. Ed grew up in rural Nebraska, completed his undergraduate studies at Iowa State, and…
-
Congratulations to the #Fungal24 Poster Award winners!
We are pleased to announce the recipients of the GSA Poster Awards for posters presented at the 32nd Fungal Genetics Conference! Undergraduate and graduate student members of GSA were eligible for the awards, and a hard-working team of judges made the determinations. Congratulations to all! Felicia Ebot Ojong, The University of Georgia My research is focused…
-
Poster presentation tips for TAGC 2024
You’ve been selected to present a poster at The Allied Genetics Conference 2024 in March—you’ve celebrated, made plans to attend, now what? This is an exciting opportunity to showcase your research and engage with fellow members of the genetics community, so you want to make sure you’re prepared. We wanted to offer you some tips…
-
Maximize your TAGC 2024 experience
A guide to all that National Harbor & DC have to offer Are you joining us for The Allied Genetics Conference 2024 in March? Make the most of your #TAGC24 experience in National Harbor! We know the science will keep you busy, but you deserve to unwind and have some fun, so we’ve curated a…
-
Early Career Leadership Spotlight: Sarah Petrosky
We’re taking time to get to know the members of the GSA’s Early Career Scientist Committees. Join us to learn more about our early career scientist advocates. Sarah PetroskyMultimedia SubcommitteeUniversity of Pittsburgh Research Interest I am interested in understanding adaptation that has been happening recently in populations by dissecting the ways that genes underlying an adaptation…
-
TAGC 2024 Early Career Award Winners
GSA is pleased to announce the winners of the early career awards presented at The Allied Genetics Conference 2024. These awards are specific to particular TAGC communities and recognize early career scientists’ outstanding work on their respective research organisms. The awardees will present their talks in keynote sessions at TAGC 2024. Don’t miss the opportunity…
-
Preeminent geneticists recognized with revamped GSA Awards
In 2022, GSA’s Board of Directors launched an audit to review the five major awards conferred by the Society. Today, we are thrilled to announce the recipients of the reimagined GSA Awards, including the new Genetics Society of America Early Career Medal. The scientists honored this year are recognized by their peers for their outstanding…
-
Fly Board funds outreach programs to spread the word about Drosophila research
In 2020, the Fly Board voted to use part of its reserve fund to support efforts to increase trainee participation as well as equity and diversity in the Drosophila community. An awards committee decides how the money will be spent each year, and from 2020–2022, the committee posted a very broad call for applications from…
-
New members of the GSA Board of Directors: 2024–2026
We are pleased to announce the election of four new leaders to the GSA Board of Directors: 2024 Vice President/2025 President Brenda Andrews Professor, University of Toronto It’s an honor to continue my association with the Society by serving as Vice President of the Board of Directors. I have broad knowledge of the ongoing activities…