Sonic hedgehog-Dependent Induction of MicroRNA 31 and MicroRNA 150 Regulates Mycobacterium bovis BCG-Driven Toll-Like Receptor 2 Signaling

Ghorpade, Devram Sampat and Holla, Sahana and Kaveri, Srini V and Bayry, Jagadeesh and Patil, Shripad A and Balaji, Kithiganahalli Narayanaswamy (2013) Sonic hedgehog-Dependent Induction of MicroRNA 31 and MicroRNA 150 Regulates Mycobacterium bovis BCG-Driven Toll-Like Receptor 2 Signaling. In: MOLECULAR AND CELLULAR BIOLOGY, 33 (3). pp. 543-556.

PDF Mol_Cel_Bio_33-3_ 543_2013.pdf - Published Version Restricted to Registered users only Download (4MB) | Request a copy

Abstract

Hedgehog (HH) signaling is a significant regulator of cell fate decisions during embryogenesis, development, and perpetuation of various disease conditions. Testing whether pathogen-specific HH signaling promotes unique innate recognition of intracellular bacteria, we demonstrate that among diverse Gram-positive or Gram-negative microbes, Mycobacterium bovis BCG, a vaccine strain, elicits a robust activation of Sonic HH (SHH) signaling in macrophages. Interestingly, sustained tumor necrosis factor alpha (TNF-alpha) secretion by macrophages was essential for robust SHH activation, as TNF-alpha(-/-) macrophages exhibited compromised ability to activate SHH signaling. Neutralization of TNF-alpha or blockade of TNF-alpha receptor signaling significantly reduced the infection-induced SHH signaling activation both in vitro and in vivo. Intriguingly, activated SHH signaling downregulated M. bovis BCG-mediated Toll-like receptor 2 (TLR2) signaling events to regulate a battery of genes associated with divergent functions of M1/M2 macrophages. Genome-wide expression profiling as well as conventional gain-of-function or loss-of-function analysis showed that SHH signaling-responsive microRNA 31 (miR-31) and miR-150 target MyD88, an adaptor protein of TLR2 signaling, thus leading to suppression of TLR2 responses. SHH signaling signatures could be detected in vivo in tuberculosis patients and M. bovis BCG-challenged mice. Collectively, these investigations identify SHH signaling to be what we believe is one of the significant regulators of host-pathogen interactions.

Item Type:	Journal Article
Publication:	MOLECULAR AND CELLULAR BIOLOGY
Publisher:	AMER SOC MICROBIOLOGY
Additional Information:	Copy right for this article belongs to the AMER SOC MICROBIOLOGY, 1752 N ST NW, WASHINGTON, DC 20036-2904 USA
Department/Centre:	Division of Biological Sciences > Microbiology & Cell Biology
Date Deposited:	13 Aug 2015 09:05
Last Modified:	13 Aug 2015 09:05
URI:	http://eprints.iisc.ac.in/id/eprint/52095

Actions (login required)

View Item