The research team led by Dr. Tim, Yue Him Wong, associate professor from Institute for Advanced Study of Shenzhen University has recently investigated the functional specialization of interna rootlets of the parasitic barnacleParasacculina sinensisentangled within host hepatopancreas, eyestalk, and claw muscle fibers. In the presented study, Dr. Wong and his team identified putative secretory proteins that may regulate host immune system, molting, and metabolism in the crabLeptodius exaratus, elucidating potential mechanisms of host manipulation. The results were published in BMC Genomics with the article titled "Transcriptome analysis of interna rootlets of the rhizocephalanParasacculina sinensisreveals potential mechanisms of parasite host control", in which post-doctoral researcher Dr. Wenjie Li served as first author and Dr. Wong as corresponding author, with Shenzhen University as their affiliation.
Rhizocephalan barnacles, characterized by extreme morphological simplification, predominantly infect decapod crustaceans. While phylogenetically a clade of Cirripedia, they morphologically resemble more like a flowering plant than an animal, not to mention barnacle as its close relative. These parasites not only extract nutrients but also manipulate host morphology, physiology, and behavior, including inducing "feminization" of male crabs and disrupting host reproduction, growth, and molting. Prior to this study, the histological characteristics ofP. sinensisinterna rootlets, their tissue-specific functional differentiation within hosts, and molecular mechanisms underlying immune evasion and reproductive interference remained unclear. The current work revealed that the interna comprises an interconnected F-actin nodal network, lipid droplets and nuclei. Comparative transcriptomic profiling of interna from hepatopancreas, muscle, and eyestalk tissues demonstrated that core highly expressed genes were predominantly associated with metabolic processes, developmental regulation, and signal transduction, with functional divergence observed across different host tissues. The study identified multiple interna-specific secretory protein domains implicated in immune system (particularly the crustacean proPO system), lipid metabolism (ML domains), and ecdysis regulation. These findings not only advance our understanding of arthropod parasitic strategies and host-parasite interactions but also provide novel insights into the evolutionary trajectory of rhizocephalan parasitism.
This research was supported by grants from the Guangdong Major Project of Basic and Applied Basic Research, the National Science Foundation of China General Project, and the Innovation Team Project of Universities in Guangdong Province.
