Thursday, August 7, 2025
Science
No Result
View All Result
  • Login
  • HOME
  • SCIENCE NEWS
  • CONTACT US
  • HOME
  • SCIENCE NEWS
  • CONTACT US
No Result
View All Result
Scienmag
No Result
View All Result
Home Science News Marine

Advances in understanding the evolution of stomach loss in agastric fishes

April 23, 2024
in Marine
Reading Time: 3 mins read
0
Novel Genotypic Convergence Associated with Stomach Loss in Agastric Fishes
66
SHARES
603
VIEWS
Share on FacebookShare on Twitter
ADVERTISEMENT
ADVERTISEMENT

Living beings can evolve to lose biological structures due to potential survival benefits from such losses. For example, certain groups of ray-finned fishes show such regressive evolution—medakas, minnows, puffera, and wrasses do not have a stomach in the gastrointestinal tract, making them agastric or stomachless fishes. However, the specific evolutionary mechanisms underlying the evolution of agastric fishes remains unclear.

Novel Genotypic Convergence Associated with Stomach Loss in Agastric Fishes

Credit: Tokyo tech

Living beings can evolve to lose biological structures due to potential survival benefits from such losses. For example, certain groups of ray-finned fishes show such regressive evolution—medakas, minnows, puffera, and wrasses do not have a stomach in the gastrointestinal tract, making them agastric or stomachless fishes. However, the specific evolutionary mechanisms underlying the evolution of agastric fishes remains unclear.

Studies about Slc26a9—a molecular transporter highly expressed in the stomach of many species—in fishes provided the initial clue. Researchers in Tokyo Institute of Technology (Tokyo Tech), Mayo Clinic College of Medicine, and Atmosphere and Ocean Research Institute, The University of Tokyo found that the slc26a9 gene was absent in many agastric ray-finned fishes but present in many gastric ray-finned fishes. These findings led them to ponder if more genes required for gastric function were absent in agastric fishes. Could such convergent gene losses account for stomach loss in agastric fishes?

A team of scientists from Japan and the USA, led by Associate Professor Akira Kato from Tokyo Tech, sought to answer this question. Kato explains, “We compared gene losses between agastric and gastric ray-finned fishes and identified additional genes co-deleted in agastric fishes.” Accordingly, the researchers identified several genes required for gastric functions that are co-deleted or pseudogenized (gene inactivation through mutations resulting in pseudogenes) in agastric fishes compared to gastric fishes, namely slc26a9, kcne2, cldn18a, and vsig1. Their findings are published in Communications Biology. 

Specifically, they identified four gene deletions—slc26a9, kcne2, cldn18a, and vsig1—resulting in a reduction or loss of stomach structure in ray-finned fishes through comparative genomic analyses (a set of experiments for comparing similarities and differences among different genomes). Not surprisingly, each of these four genes codes for essential gastric functions. slc26a9 codes for the chlorine ion channel transporter.  kcne2 codes for a regulatory subunit of the potassium ion channel.  slc26a9 and kcne2 functions are, thus, essential for secretions of gastric acids, such as hydrochloric acid.  cldn18a similarly codes for a barrier protecting the gastric cells from acid-induced damage from hydrogen ions, while vsig1 codes for controlling stomach development.

In addition, the researchers found that agastric egg-laying mammals, such as echidna and platypus, also have kcne2 and vsig1 either deleted or pseudogenized. Moreover, the researchers discovered that cldn18, if present in agastric bony fishes, is mutated compared to gastric fishes. All these findings indicate that the gene losses correlated with stomach loss represent a genotypic convergence.

Furthermore, they observed that the gastric fish, stickleback, expressed kcne2, pga, pgc, vsig1, and cldn18a in organs other than the stomach, indicating gene functions other than gastric functions. They deduced that agastric fishes could possess other genes to compensate for such gene functions, facilitating the observed gene losses. 

Kato concludes, “We identified novel genes absent in agastric fishes among four major bony fish lineages, which suggests a convergent evolution scenario in the context of stomach loss. Our findings, thus, imply that a similar cassette of gene losses occurred independently during or after stomach loss in the several agastric fish groups.” Indeed, this study is a milestone in understanding the novel genotypic convergence that fine-tuned the agastric fish body to suit its specific ecological niche. 



Journal

Communications Biology

DOI

10.1038/s42003-024-06103-x

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Convergent gene losses and pseudogenizations in multiple lineages of stomachless fishes

Article Publication Date

3-Apr-2024

Share26Tweet17
Previous Post

AIP Appoints Alejandro de la Puente as Director of the Society of Physics Students and AIP Student Engagement Officer

Next Post

Aerogel-based PCMs improve thermal management, reduce microwave emissions in electronic devices

Related Posts

blank
Marine

What Gives Chiton Teeth Their Iron-Strong Toughness?

August 7, 2025
blank
Marine

Seals on the Move: Tracking Their Coastal Journeys

August 7, 2025
blank
Marine

Catalytic Reactive Membranes: Designing Next-Gen Water Filters

August 7, 2025
blank
Marine

Illuminating Love: Insights into Medaka Courtship Behavior Revealed

August 7, 2025
blank
Marine

Chagos Study Underscores Importance of Extensive Marine Protected Areas

August 7, 2025
blank
Marine

Global Tuna Fleet Dynamics Vary Across Continents

August 7, 2025
Next Post
Even in extreme temperature conditions, the neural network-like aerogel-based composite PCMs work to improve the thermal management, solar-thermal conversion and microwave absorption in electronic devices.

Aerogel-based PCMs improve thermal management, reduce microwave emissions in electronic devices

  • Mothers who receive childcare support from maternal grandparents show more parental warmth, finds NTU Singapore study

    Mothers who receive childcare support from maternal grandparents show more parental warmth, finds NTU Singapore study

    27531 shares
    Share 11009 Tweet 6881
  • University of Seville Breaks 120-Year-Old Mystery, Revises a Key Einstein Concept

    942 shares
    Share 377 Tweet 236
  • Bee body mass, pathogens and local climate influence heat tolerance

    641 shares
    Share 256 Tweet 160
  • Researchers record first-ever images and data of a shark experiencing a boat strike

    506 shares
    Share 202 Tweet 127
  • Warm seawater speeding up melting of ‘Doomsday Glacier,’ scientists warn

    310 shares
    Share 124 Tweet 78
Science

Embark on a thrilling journey of discovery with Scienmag.com—your ultimate source for cutting-edge breakthroughs. Immerse yourself in a world where curiosity knows no limits and tomorrow’s possibilities become today’s reality!

RECENT NEWS

  • Divisive Speech Skews Social Experience at Mass Event
  • Ultrahigh-Performance XYθz Nanopositioner Revolutionized
  • Trauma and Stress Coping in Exercising vs. Non-Exercising Students Post-Earthquake
  • Unprecedented Large-Scale Aquifer Recovery Achieved

Categories

  • Agriculture
  • Anthropology
  • Archaeology
  • Athmospheric
  • Biology
  • Bussines
  • Cancer
  • Chemistry
  • Climate
  • Earth Science
  • Marine
  • Mathematics
  • Medicine
  • Pediatry
  • Policy
  • Psychology & Psychiatry
  • Science Education
  • Social Science
  • Space
  • Technology and Engineering

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 4,859 other subscribers

© 2025 Scienmag - Science Magazine

Welcome Back!

Login to your account below

Forgotten Password?

Retrieve your password

Please enter your username or email address to reset your password.

Log In
No Result
View All Result
  • HOME
  • SCIENCE NEWS
  • CONTACT US

© 2025 Scienmag - Science Magazine

Discover more from Science

Subscribe now to keep reading and get access to the full archive.

Continue reading