Characterization of white shrimp Litopenaeus vannamei integrin β and its role in immunomodulation by dsRNA-mediated gene silencing

Dev Comp Immunol. 2013 Jun;40(2):167-79. doi: 10.1016/j.dci.2013.01.001. Epub 2013 Jan 31.

Abstract

The full sequence of white shrimp Litopenaeus vannamei integrin β (LV-B) is 2879bp which encodes 787 amino acids (aa) of the open reading frame (ORF). The mature protein (764 aa) contains (1) an extracellular domain (ED) of 692 aa, (2) a transmembrane domain (TD) of 23 aa, and (3) a cytoplasmic domain (CD) of 49 aa. The cloned LV-B grouped together with crayfish Pacifastacus leniusculus integrin β (PL-B1), but was far away from vertebrate integrin β1, β3, β5, β6, β7, and β8, and another L. vannamei integrin β (LV). A Southern blot analysis indicated that the cloned LV-B was a single copy of genomic DNA. LV-B mRNA was expressed in all tissues, and was highly expressed in haemocytes. LV-B was downregulated in shrimp 24 and 96h after having received white spot syndrome virus (WSSV). LV-B expression by haemocytes of shrimp was higher in the postmoult (A and B) stage, and lower in the premoult (D2/D3) stage. LV-B expression was significantly higher by shrimp reared in 2.5‰ and 5‰ salinities. Shrimp injected with integrin β dsRNA showed gene silencing of integrin β after 36h. LV-B-silenced shrimp showed decreased hyaline cells (HCs), granular cells (GCs, including semi-granular cells), the total haemocyte count (THC), respiratory bursts (RBs), and lysozyme activity, but showed increased RB/HC, superoxide dismutase (SOD) activity/HC, and the phenoloxidase (PO) activity/GC. LV-B-silenced shrimp showed upregulated expressions of lipopolysaccharide- and β-glucan-binding protein (LGBP), peroxinectin (PX), prophenoloxidase I (proPO I), proPO II, proPO-activating enzyme (ppA), α2-macroglobulin (α2-M), cytMnSOD, mtMnSOD, and heat shock protein 70 (HSP70). It was concluded that integrin β plays important roles in proPO activation, phagocytosis, and the antioxidant system for immunomodulation in shrimp.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antioxidants / metabolism
  • Arthropod Proteins / chemistry
  • Arthropod Proteins / physiology*
  • Base Sequence
  • Conserved Sequence
  • Gene Dosage
  • Gene Expression
  • Hemocytes / immunology
  • Hemocytes / metabolism
  • Hemocytes / virology
  • Host-Pathogen Interactions
  • Immunomodulation*
  • Integrin beta Chains / chemistry
  • Integrin beta Chains / physiology*
  • Molecular Sequence Data
  • Molting
  • Organ Specificity
  • Penaeidae / physiology*
  • Penaeidae / virology
  • Phylogeny
  • RNA Interference*
  • RNA, Double-Stranded / genetics*
  • Respiratory Burst
  • Salinity
  • White spot syndrome virus 1 / immunology

Substances

  • Antioxidants
  • Arthropod Proteins
  • Integrin beta Chains
  • RNA, Double-Stranded