title: Molecular cloning, expression pattern analysis of porcine Rb1 gene and its regulatory roles during primary dedifferentiated fat cells adipogenic differentiation.
abstract: Adipocytes are the main constituent of adipose tissue and are considered to be a corner stone in the homeostatic control of whole body metabolism. Recent reports evidenced that retinoblastoma 1 (Rb1) gene plays an important role in fat development and adipogenesis in mice. Here, we cloned the partial cDNA sequences of the porcine Rb1 gene which contains the complete coding sequences (CDS) of 2820bp encoding a protein of 939 amino acids. Bioinformatic analysis revealed that the CDS of porcine Rb1 was highly identical with those of cattle, human and mice. The porcine Rb1 has three typical conserved structural domains, including Rb-A pocket domain, CYCLIN domain and C-terminus domain, and the phylogenetic tree indicates a closer genetic relationship with cattle and human. Tissue distribution analysis showed that Rb1 expression appeared to be ubiquitously in various tissues, being higher in heart, liver, muscle, and stomach. Furthermore, significant downregulation of Rb1 was found at the initial stage of dedifferentiated fat (DFAT) cells adipogenic differentiation. With the knockdown of the Rb1 expression by siRNA, the number of DFAT cells recruited to white rather than brown adipogenesis was promoted, and mRNA levels of adipogenic markers, such as PPARγ, aP2, LPL and adiponectin and protein expression of PPARγ and adiponectin were increased after hormone stimulation. The underlying mechanisms may be that knockdown of Rb1 promotes the mitotic clonal expansion and PPARγ expression by derepressing the transcriptional activity of E2F so as to facilitate the first steps of adipogenesis. In summary, we cloned and characterized an important negative regulator in adipogenic commitment of porcine DFAT cells.
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, People's Republic of China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Pei
authors.initials: P
authors.lastname: Luo
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Xuewu
authors.initials: X
authors.lastname: Peng
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Tongxing
authors.initials: T
authors.lastname: Song
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Yuanfei
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Hongkui
authors.initials: H
authors.lastname: Wei
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, People's Republic of China. Electronic address: pengjian@mail.hzau.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Peng
authors.affiliation: Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, People's Republic of China. Electronic address: jiangsiwen@mail.hzau.edu.cn.
authors.forename: Siwen
authors.initials: S
authors.lastname: Jiang
mesh_terms: D017667:Adipocytes / Q000166:cytology* / Q000378:metabolism; D050156:Adipogenesis / Q000502:physiology*; D052242:Adiponectin / Q000378:metabolism; D000273:Adipose Tissue / Q000166:cytology* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D015153:Blotting, Western; D002417:Cattle; D002454:Cell Differentiation; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D015536:Down-Regulation; D005434:Flow Cytometry; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D047495:PPAR gamma / Q000235:genetics; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D016160:Retinoblastoma Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013552:Swine
chemical_list: D052242:Adiponectin; D018076:DNA, Complementary; D047495:PPAR gamma; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D016160:Retinoblastoma Protein
keywords: Adipogenic commitment; Dedifferentiated fat cells; Molecular cloning; Porcine; Rb1