Scientists discover new protein with key immunological role in rainbow trout gills
The presence and activation of new TRIM proteins in rainbow trout gills in response to bacterial and viral stimuli could have implications for the mechanisms of innate immunity.
Published
The study of cell subpopulations and molecular components involved in the physiological response has provided important insights into the evolution of the immune system in vertebrate animals, reports Fish Farming Expert's Chilean sister site, Salmonexpert.cl.
For example, the Tripartite Motif (TRIM) protein family has been associated with several biological processes, including apoptosis, cell proliferation and differentiation, ontogenetic development, and modulation of the immune response by coordinating inflammation-related processes such as antiviral restriction, autophagy, and inflammasome activation.
Although this group of proteins has been described in salmonids, its molecular mechanisms and functions are still being investigated in aquatic animals.
Regarding this last point, a group of Chilean and Irish scientists carried out a study with the aim of characterising new TRIM proteins involved in the innate immunity of rainbow trout gill cells (RTgill-W1 and primary cultures) stimulated with lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (poly I:C).
In addition, they performed an in vivo experiment with rainbow trout to detect TRIM proteins after challenge with Flavobacterium psychrophilum.
Gene expression
The in vitro results showed that OmTRIM25, a novel TRIM protein discovered by the researchers, triggered LPS-induced expression of pro-inflammatory cytokines such as TNF-α2 and IL-1β. “Furthermore, in the fish experiment, OmTRIM25 and finTRIM2 showed increased gene expression in the gills two days post-infection (dpi), while IL-1β and TNF-α2 showed increased gene expression at four and six days post-infection, respectively,” the authors explained.
In other words, the experts demonstrated that gill tissue expressed novel TRIM proteins not previously described in rainbow trout; that their expression can be induced by a specific molecular pattern associated with viral or bacterial pathogens (in vitro), and that they exhibited specific, time-dependent peaks of expression in the gills of rainbow trout following bacterial infection with F. psychrophilum.
Finally, the scientists noted that these current findings provide new insights into the role of TRIM proteins in rainbow trout immunology and the possible molecular mechanisms that support their function.
Read the full article titled “Novel TRIM Proteins Modulating the Innate Immune Response of Rainbow Trout (Oncorhynchus mykiss)” here.
