title: Expression of cytoskeletal and molt-related genes is temporally scheduled in the hypodermis of the crayfish Procambarus clarkii during premolt.
abstract: The rigid crustacean exoskeleton, the cuticle, is composed of the polysaccharide chitin, structural proteins and mineral deposits. It is periodically replaced to enable growth and its construction is an energy-demanding process. Ecdysis, the shedding event of the old cuticle, is preceded by a preparatory phase, termed premolt, in which the present cuticle is partially degraded and a new one is formed underneath it. Procambarus clarkii (Girard 1852), an astacid crustacean, was used here to comprehensively examine the changing patterns of gene expression in the hypodermis underlying the cuticle of the carapace at seven time points along ~14 premolt days. Next generation sequencing was used to construct a multi-tissue P. clarkii transcript sequence assembly for general use in a variety of transcriptomic studies. A reference transcriptome was created here in order to perform digital transcript expression analysis, determining the gene expression profiles in each of the examined premolt stages. The analysis revealed a cascade of sequential expression events of molt-related genes involved in chitin degradation, synthesis and modification, as well as synthesis of collagen and four groups of cuticular structural genes. The new description of major transcriptional events during premolt and the determination of their timing provide temporal markers for future studies of molt progress and regulation. The peaks of the expression of the molt-related genes were preceded by expression peaks of cytoskeletal genes that are hypothesized to be essential for premolt progress through regulating protein synthesis and/or transport, probably by remodeling the cytoskeletal structure.
authors.affiliation: Israel Oceanographic and Limnological Research, P.O.B. 8030, Haifa 31080, Israel.
authors.forename: Moshe
authors.initials: M
authors.lastname: Tom
authors.affiliation: Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, Trieste, 34127, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Manfrin
authors.affiliation: Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, 701 East Pratt Street, Baltimore, MD 21202, USA.
authors.forename: Sook J
authors.initials: SJ
authors.lastname: Chung
authors.affiliation: Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel.
authors.forename: Amir
authors.initials: A
authors.lastname: Sagi
authors.affiliation: Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, Trieste, 34127, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Gerdol
authors.affiliation: Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, Trieste, 34127, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: De Moro
authors.affiliation: Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, Trieste, 34127, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Pallavicini
authors.affiliation: Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, Trieste, 34127, Italy.
authors.forename: Piero G
authors.initials: PG
authors.lastname: Giulianini
mesh_terms: D000818:Animals; D003400:Astacoidea / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D002686:Chitin / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D059014:High-Throughput Nucleotide Sequencing; D018978:Molting / Q000235:genetics / Q000502:physiology*; D011506:Proteins / Q000378:metabolism; D059467:Transcriptome
chemical_list: D011506:Proteins; D002686:Chitin
keywords: Cytoskeletal genes; Gene expression; Hypodermis; Premolt; Procambarus clarkii