As appearing in source.colostate.edu | June 17, 2025 | By Josh Rhoten
Crab Lab offers gateway into marine biology-type research in landlocked Colorado
Landlocked Colorado State University is not the first institution you may think of to study marine biology. But far from any ocean shore, Talia Head recently finished her research into Gecarcinus lateralis here – more commonly known as the blackback land crab.
Head graduated this spring with a Ph.D. from the Department of Biology. For the past five years – and as an undergrad well before that – she worked in CSU’s “Crab Lab” under Professor Donald Mykles. That team studies the complicated life cycle process of molting crabs across several key cellular mechanisms. They are particularly interested in how the animal’s organs and hormones coordinate the timing of a delicate chemical dance when a crab shrugs off its hard exterior shell and begins to grow a new, larger protective barrier later in life.
Insights into how a crab regulates those physiological processes could improve aquaculture production of them as a food source or aid in the development of pest control for insects that undergo similar molting processes, Head said. Understanding the ways crabs regulate their growth through protein synthesis could also be relevant for the treatment of cancer where cells grow too fast or ignore regulation signals.
Head’s work at CSU touched on many of those topics during her dissertation and in findings recently published in The Journal of Experimental Biology. She was the first author on that paper, which explores how the hormone ecdysteroid triggers the molting process and how another hormone – MIH – prevents it by activating genes to produce two key proteins called PKG1 and PKG2.
“The whole cellular system we study in the lab is such a cool one. Crabs need to time this simple, yet intricate process well to survive the transition into their new protective shell and continue to grow,” she said. “We are working to understand how those proteins are involved and connect to the larger process which can go on for weeks and involves several organs, hormones and secreted chemicals.”
Studying crustacean molting physiology and genetics in Department of Biology
Head said the work illustrates how PKG1 and PKG2 are uniquely paired in this transition process. To better understand their contributions and relationship to each other, she used pharmaceutical “off switches” to alternately block both protein’s activity in blackback crabs and in another crab species for comparison.
She said they found when PKG1 was blocked the crabs started making more hormones which start the molting process.
“However, when we inhibited PKG2, which did not seem to be doing anything at first, we found that molting hormone syntheses decreased,” Head said. “Our work shows that these two genes are balancing each other. Where PKG1 is limiting growth PKG2 is stimulating just enough hormone synthesis for growth in the background to avoid a premature molting phase and to support other key functions like reproduction that it is associated with.”
Head added that these genes are common in several other species including mammals. That means research into how these genes are paired together could be useful in a variety of biology projects beyond crabs.
“We hope to publish another paper on this topic soon that deals with proteomics and extensively outlines those genes’ composition, structure, expression and interactions completely,” Head said. “There is so much data to go through, but now that we know what these proteins are doing, the challenge is understanding how they are doing it.”
Head originally joined the Crab Lab in 2010 after Mykles visited a freshman course and invited her and fellow students to join his research team. Head seized on the opportunity and wound up working in the lab – one of the largest on campus – for all four years of her undergrad. Then, after a stop at Cal Poly San Luis Obispo to earn her master’s, she returned to CSU to get her Ph.D. with Mykles.
Mykles said Head is a highly creative and talented scientist who will continue to make significant contributions to the field.
“Talia is an impressive researcher as the findings in this paper show. I look forward to seeing what she can accomplish next and look forward to potentially working with her again soon – perhaps as a faculty member leading her own research team into this complex and crucial research questions,” he said. “Talia joined my lab as an undergraduate because of her interest in marine biology. It’s wonderful to see how she has fulfilled that dream.”
Head’s next stop? A position as a postdoctoral researcher at Washington State University to study the effects of heat shock – genes that activate in response to stress – on the California mussel. That research is important because as a keystone species the mussel has an outsized impact on the rocky intertidal zone of the Pacific coast. The fact that the host university is in the city of Pullman – almost 300 miles from the nearest ocean – isn’t lost on her at all.