In vivo RNA interference demonstrates a role for Nramp1 in modifying susceptibility to type 1 diabetes.
Type 1 diabetes is an autoimmune disease influenced by multiple genetic loci. Although more than 20 insulin-dependent diabetes (Idd) loci have been implicated in the nonobese diabetic (NOD) mouse model, few causal gene variants have been identified. Here we show that RNA interference (RNAi) can be used to probe candidate genes in this disease model. Slc11a1 encodes a phagosomal ion transporter, Nramp1, that affects resistance to intracellular pathogens and influences antigen presentation. This gene is the strongest candidate among the 42 genes in the Idd5.2 region; a naturally occurring mutation in the protective Idd5.2 haplotype results in loss of function of the Nramp1 protein. Using lentiviral transgenesis, we generated NOD mice in which Slc11a1 is silenced by RNAi. Silencing reduced the frequency of type 1 diabetes, mimicking the protective Idd5.2 region. Our results demonstrate a role for Slc11a1 in modifying susceptibility to type 1 diabetes and illustrate that RNAi can be used to study causal genes in a mammalian model organism.
Center for Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. skissler@mit.edu
Stephan
S
Kissler
Patrick
P
Stern
Kazue
K
Takahashi
Kara
K
Hunter
Laurence B
LB
Peterson
Linda S
LS
Wicker
D000818:Animals; D027682:Cation Transport Proteins / Q000235:genetics*; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D034622:RNA Interference; D000099173:Natural Resistance-associated Macrophage Protein 1
D027682:Cation Transport Proteins; D000099173:Natural Resistance-associated Macrophage Protein 1