Abstract
The rat sarcoma-extracellular signal regulated kinase mitogen-activated protein kinases pathway, one of the most ancient signaling pathways, is crucial for the defense against Bombyx mori nucleopolyhedrovirus (BmNPV) infection. Sprouty (Spry) proteins can inhibit the activity of this pathway by receptor tyrosine kinases. We cloned and identified a new B. mori gene with a Spry domain similar to the Spry proteins of other organisms, such as fruitfly, mouse, human, chicken, Xenopus and zebrafish, and named it BmSpry. The gene expression analysis showed that BmSpry was transcribed in all of the examined tissues and in all developmental stages from embryo to adult. BmSpry also induced expression of BmNPV in the cells. Our results indicated: (1) the knock-down of BmSpry led to increased BmNPV replication and silkworm larvae mortality; (2) over-expression of BmSpry led to reduced BmNPV replication; and (3) BmSpry regulated the activation of ERK and inhibited BmNPV replication. These results showed that BmSpry plays a crucial role in the antiviral defense of the silkworm both in vitro and in vivo.
Highlights
Sprouty (Spry) is a general inhibitor of receptor tyrosine kinases (RTKs), first identified in fibroblast growth factor (FGF)-stimulated tracheal branching during Drosophila development [1]
Data are given as mean 6SD (n = 3). (B) Nm DZ silkworms treated with double-stranded RNA (dsRNA) against the indicated genes were infected with Bombyx mori nucleopolyhedrovirus (BmNPV) (106 pfu/mL) by stab inoculation for 3 days and processed for quantitative PCR (qPCR)
Data are given as mean 6SD (n = 3). (C) Analysis of the expression level of BmSpry in Nm DZ and the mutant DZ SN
Summary
Sprouty (Spry) is a general inhibitor of receptor tyrosine kinases (RTKs), first identified in fibroblast growth factor (FGF)-stimulated tracheal branching during Drosophila development [1]. Mammalian genomes contain four Spry genes (Spry 1–4) encoding proteins (32–34 kDa) smaller than Drosophila melanogaster Spry (63 kDa) [8]. Drosophila Spry and vertebrate Spry proteins have a highly conserved C-terminal cysteine-rich region responsible for the membrane localization of Spry through palmitoylation [9]. A short region in the N terminus contains a conserved tyrosine residue, which mediates the interaction with its signaling molecules that contain Src-homology-2 domains [10,11,12,13,14,15]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
