Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Key Reproductive Hormone in Oldest Vertebrate ID’d

08.10.2010
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. Sower’s ongoing work on hagfish gonadotropin has also been funded in part by the New Hampshire Agricultural Experiment Station.

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.

Beth Potier | Newswise Science News
Further information:
http://www.unh.edu

More articles from Life Sciences:

nachricht Tag it EASI – a new method for accurate protein analysis
20.06.2018 | Max-Planck-Institut für Biochemie

nachricht How to track and trace a protein: Nanosensors monitor intracellular deliveries
19.06.2018 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Creating a new composite fuel for new-generation fast reactors

20.06.2018 | Materials Sciences

Game-changing finding pushes 3D-printing to the molecular limit

20.06.2018 | Materials Sciences

Could this material enable autonomous vehicles to come to market sooner?

20.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>