title: Pig lacks functional NLRC4 and NAIP genes.
abstract: The NLRC4 inflammasome, which recognizes flagellin and components of the type III secretion system, plays an important role in the clearance of intracellular bacteria. Here, we examined the genomic sequences carrying two genes encoding key components of the NLRC4 inflammasome-NLR family, CARD-containing 4 (NLRC4), and NLR apoptosis inhibitory protein (NAIP)-in pigs. Pigs have a single locus encoding NLRC4 and NAIP. Comparison of the sequences thus obtained with the corresponding regions in humans revealed the deletion of intermediate exons in both pig genes. In addition, the genomic sequences of both pig genes lacked valid open reading frames encoding functional NLRC4 or NAIP protein. Additional pigs representing multiple breeds and wild boars also lacked the exons that we failed to find through genome sequencing. Furthermore, neither the NLRC4 nor the NAIP gene was expressed in pigs. These findings indicate that pigs lack the NLRC4 inflammasome, an important factor involved in monitoring bacterial proteins and contributing to the clearance of intracellular pathogens. These results also suggest that genetic polymorphisms affecting the molecular functions of TLR2, TLR4, TLR5, and other pattern recognition receptors associated with the recognition of bacteria have a more profound influence on disease resistance in pigs than in other species.
authors: Animal Bioregulation Unit, Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki, 305-8634, Japan.|Present address: National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo, 162-8640, Japan.
authors: Chisato
authors: C
authors: Sakuma
authors: Animal Research Division, Institute of Japan Association for Techno-innovation in Agriculture, Forestry and Fisheries, 446-1 Ippaizuka, Kamiyokoba, Tsukuba, Ibaraki, 305-0854, Japan.
authors: Daisuke
authors: D
authors: Toki
authors: Animal Bioregulation Unit, Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki, 305-8634, Japan.
authors: Hiroki
authors: H
authors: Shinkai
authors: Animal Bioregulation Unit, Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki, 305-8634, Japan.
authors: Takato
authors: T
authors: Takenouchi
authors: Animal Bioregulation Unit, Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki, 305-8634, Japan.
authors: Mitsuru
authors: M
authors: Sato
authors: Animal Bioregulation Unit, Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki, 305-8634, Japan.
authors: Hiroshi
authors: H
authors: Kitani
authors: Animal Bioregulation Unit, Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2 Owashi, Tsukuba, Ibaraki, 305-8634, Japan. huenishi@affrc.go.jp.
authors: Hirohide
authors: http://orcid.org/0000-0002-3899-9580
authors: H
authors: Uenishi
mesh_terms: D000818:Animals; D001419:Bacteria / Q000276:immunology*; D053468:CARD Signaling Adaptor Proteins / Q000235:genetics*; D002478:Cells, Cultured; D016678:Genome; D007113:Immunity, Innate / Q000276:immunology*; D058847:Inflammasomes / Q000235:genetics* / Q000276:immunology; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D051616:Neuronal Apoptosis-Inhibitory Protein / Q000235:genetics*; D013552:Swine; D051193:Toll-Like Receptors / Q000235:genetics / Q000378:metabolism
chemical_list: D053468:CARD Signaling Adaptor Proteins; D058847:Inflammasomes; D051616:Neuronal Apoptosis-Inhibitory Protein; D051193:Toll-Like Receptors
keywords: Genome sequencing; Inflammasome; Pattern recognition receptors; Swine