Cloning, characterization and effect of TmPGRP-LE gene silencing on survival of Tenebrio molitor against Listeria monocytogenes infection.
Peptidoglycan recognition proteins (PGRPs) are a family of innate immune molecules that recognize bacterial peptidoglycan. PGRP-LE, a member of the PGRP family, selectively binds to diaminopimelic acid (DAP)-type peptidoglycan to activate both the immune deficiency (Imd) and proPhenoloxidase (proPO) pathways in insects. A PGRP-LE-dependent induction of autophagy to control Listeria monocytogenes has also been reported. We identified and partially characterized a novel PGRP-LE homologue, from Tenebrio molitor and analyzed its functional role in the survival of the insect against infection by a DAP-type PGN containing intracellular pathogen, L. monocytogenes. The cDNA is comprised of an open reading frame (ORF) of 990 bp and encodes a polypeptide of 329 residues. TmPGRP-LE contains one PGRP domain, but lacks critical residues for amidase activity. Quantitative RT-PCR analysis showed a broad constitutive expression of the transcript at various stages of development spanning from larva to adult. RNAi mediated knockdown of the transcripts, followed by a challenge with L. monocytogenes, showed a significant reduction in survival rate of the larvae, suggesting a putative role of TmPGRP-LE in sensing and control of L. monocytogenes infection in T. molitor. These results implicate PGRP-LE as a defense protein necessary for survival of T. molitor against infection by L. monocytogenes.
Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, Korea. hanys@jnu.ac.kr.
Hamisi
H
Tindwa
Bharat Bhusan
BB
Patnaik
Dong Hyun
DH
Kim
Seulgi
S
Mun
Yong Hun
YH
Jo
Bok Luel
BL
Lee
Yong Seok
YS
Lee
Nam Jung
NJ
Kim
Yeon Soo
YS
Han
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics* / Q000302:isolation & purification; D003001:Cloning, Molecular; D020868:Gene Silencing; D008089:Listeria monocytogenes / Q000235:genetics* / Q000472:pathogenicity; D008088:Listeriosis / Q000235:genetics / Q000382:microbiology; D013712:Tenebrio / Q000235:genetics / Q000382:microbiology*
D002352:Carrier Proteins; C118897:peptidoglycan recognition protein