Zeng and his colleagues chose to focus on the gland cells that produce the fishs slick compound, and in their September 20 paper in Current Biology, they find that these slime cells differ in size and produce in a different way sized threads depending on the size of the hagfish, with larger hagfish having much larger thread-producing cells than would be anticipated based on body size alone. These larger cells produce longer and thicker threads, which lead to more viscous slime capable of preventing even the most imposing underwater predators. In this particular research study, were connecting dots about body size, and about the size of the cell that makes the thread, and then about the thread. That indicates the cells end up being actually large to produce the threads. What does that mean?YZ: That means the cell should be truly specialized and … when the cell grows in size, ending up being very big, it needs a more powerful supply system.
Hagfish are infamous for their defensive slime, which can swell from a little secretion to a carload of goo in a split second. The slime is comprised of a winding web of fibrous protein threads that trap the surrounding seawater, hence change it into a malicious mucous that suffocates the gills and jaws of attacking predators. courtesy of yu zengThe biology of this slime has actually long amazed materials researchers and evolutionary biologists alike, including Yu Zeng, an evolutionary biologist at Chapman University in California. Zeng and his associates decided to concentrate on the gland cells that produce the fishs slick compound, and in their September 20 paper in Current Biology, they find that these slime cells vary in size and produce differently sized threads depending on the size of the hagfish, with bigger hagfish having much bigger thread-producing cells than would be anticipated based on body size alone. These larger cells produce longer and thicker threads, which cause more thick slime efficient in discouraging even the most enforcing undersea predators. Zeng posits that the cells size may have progressed to fend off the different predators of hagfish– both little and large. The Scientist spoke to Zeng about the new paper and hagfishes in general to find out more about the slimy superpowers of these bizarre deep sea fish. The Scientist: What interested you in studying the cells of hagfish in particular?Yu Zeng: Hagfishes are simply weird. Theyre so distant from our mundane human life since they live in the deep ocean. They do not have a face, dont have eyes, and look alien. We understand actually little about their biography, so anything about hagfish is, by default, interesting. In this specific job, we study the morphology of the cell that produces this thread. The thread is an essential component for their defensive slime, [and] is likewise a really, actually strange structure. The larger picture is … The larger hagfish it would be consumed or attacked by bigger fishes. And then the smaller sized types would be assaulted by smaller sized species of predator, and after that they reside in different depths of the ocean … Were wondering if the cell [s] that produce the threads, and then the threads themselves, alter with the body size of the hagfish. Simply put, do larger hagfishes have a stronger armor versus predators?Pacific hagfish (Eptatretus stoutii) in a netCourtesy of yu zengTS: About your research process: did you come across any challenges?YZ: I can begin with the easy difficulty that is access to specimen [s] … You can buy newly recorded specimens from fishermen, … but there is only a restricted number of types [readily available this method] … If we want to compare in between a great deal of species, then we have to sample from museum specimens. Those are preserved specimens captured by mishap during surveys throughout history. Some are 10s of years of ages. Some are delicate. In this study, my co-authors studied the one [ s] in the museum, [and] sampled the glands from pickled specimens.The 2nd difficulty is a little more like mental, since every time I see them, it simply reminds me of those alien motion pictures. They dont have a lower jaw, so when they open their mouth, it unfolds and folds from within out with two lateral jaws. It does not open up and down but unfolds. So its really unusual. And I d say a third challenge is to link all the dots throughout different levels. In this particular research study, were linking dots about body size, and about the size of the cell that makes the thread, and after that about the thread. So, I need to develop models to link these various levels. The whole animal is one level of things– thats the entire animal interacting with predators. And after that there is [the] cell– the physiology and mechanics … And then the third level, the threads. I [had] to establish a design to assist us estimate the size of the thread, because when we sample the thread, its a packed skein within the cell. Due to the fact that its extremely thin, you cant straight determine the thread. And its tough to take out … a thread and after that use microtweezers [to] unfold it, unwind it, and after that stretch it and measure it. Its almost difficult. You might break the thread at any stage … Then, when I have all this data, I need to compose scripts, like computer system programs, to do analyses.TS: Was there anything that amazed you?YZ: [The] severe allometry, [which is] basically how cell size modification [s] with body size … [for the thread-producing cells] this coefficient is larger than any formerly recorded cells. That suggests the cells become really large to produce the threads. Because cell sizes are fairly consistent in animals, this is surprising. We demonstrate how much the cell scaling goes beyond the scaling in other cases, like in [mammalian cells] [This will] assist us understand the flexibility of animal cells and provide some brand-new knowledge about the system that drives cell size advancement. TS: The paper discussed that hagfish slime threads are the largest intracellular polymer known. What does that mean?YZ: That implies the cell should be actually specialized and … when the cell grows in size, ending up being incredibly big, it needs a more effective supply system. It takes a lot of energy to grow the protein … [The cell also] requirements other mechanism [s] to be structurally strenuous … [It] will not be easily warped. We presume the development of these glands, the thread cells, are provided by other cells around [them that] pump energy towards [them] and products to make brand-new threads. The bulk of the cell is taken up by the thread … The cell nuclei [ are] actually, actually small, … less than five percent of the volume. So that indicates the cell has provided up a great deal of other organelles to be able to make the thread.Scanning electron microscopy pictures of the hagfish thread skeinsCourtesy of Gaurav Jain TS: Where do you see the future of this research study going? What would you like to check out? YZ: This paper becomes part of a job where we study how hagfish make threads. Im attempting to comprehend how this whole bundle or skein of threads establish– how it grows from little to large, and how its formed, due to the fact that to make a skein, [the thread has] to have a lot of loops, and [the cell has] to load the loops efficiently. How is the product packaging achieved within a single cell? Thats one of the ongoing directions. On a various level, I would have an interest in understanding the evolution of the thread. Whats the origin of this cell? What is the earlier type? Due to the fact that anything you look [at] that is so complex and specialized has a simple, ancestral form. Its derived from something that is not as alien, not as specialized, something more typical. That transitional process from regular, easier, less specialised form to this specialised type is interesting. And its the Mars shot. The first one I pointed out is probably the moon shot, and after that this one is the Mars shot. To comprehend the origin of these intricate structures includes a lot of fields– cell biology, biomaterials, biomechanics, geometrics, computer system science, product science– and a great deal of programming to be able to bridge all these fields together. Editors note: this interview has been edited for brevity.
