The bovine Mx1 gene: characterization of the gene structure, alternative splicing, and promoter region.
The Mx gene encodes an antiviral protein and is induced by type 1 interferons (IFNs). In this study, a new bovine Mx gene (designated Mx1B) was isolated from the endometrial cDNA library of the early pregnant cow. Although the Mx1B cDNA contained a single open reading frame (ORF) the same as the known Mx1, the 5' untranslated region (UTR) and 5' coding region of Mx1B were rather different from the corresponding regions of Mx1. Genomic structure analysis revealed that bovine Mx1B was an alternative splicing variant of Mx1 and had transcription regulatory sequences in the upstream region. RT-PCR and its sequencing identified another Mx1 splicing variant and demonstrated that these bovine Mx1 splicing variants were ubiquitously expressed in various tissues. Furthermore, it was found that all the bovine breeds investigated had identical splice sites of Mx1 and Mx1B. It is speculated that cattle have at least two functional Mx isoforms that might provide strong natural resistance to specific viruses.
Kojima
Takatoshi
T
Department of Livestock and Grassland Science, National Agricultural Research Center for Western Region, Oda, Shimane 694-0013, Japan. tkoj@affrc.go.jp
Oshima
Kazunaga
K
Watanabe
Hiroko
H
Komatsu
Masanori
M
D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D019204:GTP-Binding Proteins / Q000235:genetics* / Q000302:isolation & purification; D015870:Gene Expression; D007962:Leukocytes / Q000737:chemistry; D008969:Molecular Sequence Data; D064547:Myxovirus Resistance Proteins; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018076:DNA, Complementary; D064547:Myxovirus Resistance Proteins; D012333:RNA, Messenger; D019204:GTP-Binding Proteins