Integration of microbiome and Koch's postulates to reveal multiple bacterial pathogens of whitish muscle syndrome in mud crab, Scylla paramamosain.

Background: For more than a century, the Koch's postulates have been the golden rule for determining the causative agents in diseases. However, in cases of multiple pathogens-one disease, in which different pathogens can cause the same disease, the selection of microorganisms that regress infection is hard when Koch's postulates are applied. Microbiome approaches can obtain relatively complete information about disease-related microorganisms and can guide the selection of target microorganisms for regression infection.

A Dicer2 from Scylla paramamosain activates JAK/STAT signaling pathway to restrain mud crab reovirus.

A Dicer2 gene from Scylla paramamosain, named SpDicer2, was cloned and characterized. The full length of SpDicer2 mRNA contains a 121 bp 5'untranslated region (UTR), an open reading frame (ORF) of 4518 bp and a 3' UTR of 850 bp. The SpDicer2 protein contains seven characteristic Dicer domains and showed 34%-65% identity and 54%-79% similarity to other Dicer protein domains, respectively.