Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UNH researcher helps identify key reproductive hormone in oldest vertebrate

06.10.2010
Looking at a hagfish – an eyeless, snot-covered, worm-like scavenger of the deep –the last thing that comes to mind is sex. Yet the reproductive functioning of these ancient vertebrates is such an enduring enigma that a gold medal was once offered to anyone who could elucidate it.

Although the prize expired, unclaimed, long ago, University of New Hampshire professor of biochemistry Stacia Sower and colleagues at two Japanese universities have identified the first reproductive hormone of the hagfish – a gonadatropin -- representing a significant step toward unraveling the mystery of hagfish reproduction.

Their findings, "Evolutionary origin of a functional gonadotropin in the pituitary of the most primitive vertebrate, hagfish," were published in the journal Proceedings of the National Academies of Science (PNAS) in September.

"This is a significant breakthrough with hagfish," says Sower, who was second senior author on this paper, co-authored by principal investigator Katsuhisa Uchida and Sower's long-time collaborator Masumi Nozaki, both of Niigata University in Japan. Gonadatropins (GTHs) are a protein secreted from the pituitary, stimulating the gonads (ovaries and testes) to produce and release the sex steroid hormones which prompt their growth and maturation. GTHs are produced in response to hypothalamic gonadotropin-releasing hormone (GnRH), what Sower calls the "master molecule" for reproduction in vertebrates; its discovery remains the holy grail of understanding hagfish reproduction.

At 500 million years old, hagfish are the oldest living vertebrate, predating the dinosaurs. "They're one of evolution's great success stories," says Sower, who has devoted the majority of her 30-year career researching hagfish and the similarly un-charismatic lamprey eels. "Here's this animal with a backbone that we don't know anything about." They're notoriously difficult to study, in part because their habitat is the ocean floor at 100 meters or more.

Yet their important evolutionary position makes hagfish worthy of scientific inquiry. "We look at the evolution of the hormones and receptors and say, 'have they retrained characteristics of their ancestral forms, or are they more similar to higher vertebrates?'" says Sower. "They're a key to understanding the evolution of later evolved vertebrates."

Compounding the urgency of better understanding hagfish reproduction is their growing importance as a fishery in the Gulf of Maine. Despite their vicious nature and least appealing characteristic – the stress-induced secretion of mucous from up to 200 slime glands along their bodies – hagfish are prized, particularly in Asian markets. Their tough, soft skin is marketed as "eel" skin for wallets, belts and other items ("Because they're not going to sell something that says 'hagfish,'" says Sower, pulling out her own flawless 20-year-old eel skin wallet).

Fished in the Gulf of Maine since 1992, hagfish have been fished out of the waters off Korea and Japan and overfished on the U.S. West coast. They also play a significant role in nutrient cycling and ocean-floor clean-up, feeding primarily on dead and dying fish. Lacking knowledge on their reproductive functions – how, when and where they spawn – the hagfish could be fished to extinction, says Sower.

Sower, who directs the Center for Molecular and Comparative Endocrinology at UNH, has worked with Nozaki on hagfish reproduction since both scientists were postdoctoral researchers at the University of Washington in 1980. The two, along with Hiroshi Kawauchi of Kitasato University in Japan, have shared students and researchers through a formal collaboration that's produced more than 30 papers. It's also, notes Sower, produced many failures as they've labored to identify the hagfish GTH.

"Now we're filling in the gaps of what we know," she says.

To download a copy of the paper, go to http://www.pnas.org/content/107/36/15832.long.

This work was supported in part by a grant from the National Science Foundation.

The University of New Hampshire, founded in 1866, is a world-class public research university with the feel of a New England liberal arts college. A land, sea, and space-grant university, UNH is the state's flagship public institution, enrolling 12,200 undergraduate and 2,200 graduate students.

Photographs available to download: http://www.unh.edu/news/cj_nr/2010/oct/bp04hagfish_02.jpg

Caption: University of New Hampshire professor of biochemistry Stacia Sower and colleagues have identified the first reproductive hormone of the hagfish, the world's oldest living vertebrate. Credit: Courtesy of Stacia Sower.

http://www.unh.edu/news/cj_nr/2010/oct/bp04hagfish_01.jpg

Caption: UNH professor Stacia Sower and researchers in her lab collect hagfish from the Gulf of Maine for study. Credit: Courtesy of Stacia Sower.

http://www.unh.edu/news/cj_nr/2010/oct/bp04hagfish_03.jpg

Caption: UNH professor Stacia Sower (in orange) and researchers in her lab collect hagfish from the Gulf of Maine for study. Credit: Courtesy of Stacia Sower.

Beth Potier | EurekAlert!
Further information:
http://www.unh.edu

More articles from Life Sciences:

nachricht Rutgers scientists discover 'Legos of life'
23.01.2018 | Rutgers University

nachricht Researchers identify a protein that keeps metastatic breast cancer cells dormant
23.01.2018 | Institute for Research in Biomedicine (IRB Barcelona)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Optical Nanoscope Allows Imaging of Quantum Dots

Physicists have developed a technique based on optical microscopy that can be used to create images of atoms on the nanoscale. In particular, the new method allows the imaging of quantum dots in a semiconductor chip. Together with colleagues from the University of Bochum, scientists from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute reported the findings in the journal Nature Photonics.

Microscopes allow us to see structures that are otherwise invisible to the human eye. However, conventional optical microscopes cannot be used to image...

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Rutgers scientists discover 'Legos of life'

23.01.2018 | Life Sciences

Seabed mining could destroy ecosystems

23.01.2018 | Earth Sciences

Transportable laser

23.01.2018 | Physics and Astronomy

VideoLinks Science & Research
Overview of more VideoLinks >>>