Innate Immune System Guiding Physiological Plasticity in Invertebrates

Innate immunity serves as the first line of defense against infection in multicellular organisms. While it is the only defense system in invertebrates, it synergizes adaptive immunity in vertebrates. The plasticity of the innate immune system in invertebrates is sufficiently capable of eliminating pathogens, and perhaps more importantly discriminating them from other microorganisms. During the past two decades, the molecular structure and function of various defense components that participate in the innate immune system of invertebrates have been established. The participating defense molecules include humoral factors such as antimicrobial peptides, prophenoloxidase and reactive oxygen species, and cellular mechanisms such as nodulation, encapsulation and phagocytosis. Recently, comprehensive genomic and transcriptomic datasets have shed insight into high innate immune specificity through diversification of the immune gene repertoire in invertebrates occupying diversifying wild habitats. Furthermore, molecular resources related to innate immunity have been catalogued as a means of informed conservation planning of endangered, threatened and protected species. This has allowed unbiased phenotypic screens for many immunological traits, fostering conservation by promoting beneficial hybridization. Conversely, the innate immunity mechanism and signalling cascades leading to immune surveillance in the invertebrate host against pathogens have been explored for pest management, fitness physiological traits for selective breeding and functional genomic approaches.

The aim of this Research Topic is to provide a forum for discussing the attributes exemplifying the phenotypic plasticity in terms of innate immunity traits underlying the physiological status of invertebrates. We aim to contribute to the broader field of invertebrate conservation, by soliciting original research and state-of-the-art review articles in basic and applied entomology, molecular genetics and genomics, conservation and evolutionary biology. The sub-topics under this Research Topic may include, but not limited to:

• Innate immunity signaling cascades highlighting novel components of humoral and cell-mediated immunity
• Pathogen evasion mechanisms in invertebrate hosts and immune surveillance
• Next-Generation sequencing approaches addressing the need for informed conservation planning of invertebrate species through cataloguing of molecular resources
• Elucidation of physiological fitness traits and genomic markers for understanding the plasticity in the immune functions of invertebrates
• Novel approaches and techniques exemplifying the structural, functional and big data analysis of innate immunity leading to an expanded knowledge on the physiological mechanisms attributed to invertebrate survival