title: cDNA cloning, gene organization and variant specific expression of HIF-1 alpha in high altitude yak (Bos grunniens).
abstract: Hypoxia-inducible factor 1 (HIF-1) is a heterodimeric basic-helix-loop-helix-PER-ARNT-SIM (bHLH-PAS) transcription factor consisting of HIF-1alpha and HIF-1beta subunits. HIF-1alpha is the oxygen-regulated subunit of HIF-1, which regulates the transcription of genes involved in oxygen homeostasis in response to hypoxia. Yak (Bos grunniens), a mammal native to high altitude (HA) region ( approximately 3500-5500 m), has successfully adapted over many generations to the chronic hypoxia of HA. In the present work, cDNA encoding HIF-1alpha has been cloned from the blood of yak. Tissue specific expression of the mRNA was analyzed in blood, heart, lung, liver and kidney by RT-PCR with primers from three different regions of cDNA. The HIF-1alpha expression was liver and blood specific. The HIF-1alpha mRNA contains 823 bp long 3'UTR that is AU-rich and contains ten AUUUA pentamers and two overlapping copies of the nonamer UUAUUUAUUUAUU. Three potential microRNAs, hsa-miR-107/mmu-miR-107/rno-miR-107, hsa-miR-18b and hsa-miR-135a/mmu-miR-135a/rno-miR-135a, targeting 3'UTR of yak HIF-1alpha, were identified by using target prediction software. The CDS encodes for 823 residues of amino acids and showed 99%, 95%, 92%, 90% and 90% similarity to domestic cattle, human, plateau pika, mouse and rat HIF-1alpha, respectively. HIF-1alpha cDNA, cloned and sequenced in the present work has revealed the evolutionary conservation through multiple sequence alignment. Liver and blood specific stability of HIF-1alpha mRNA appears miR-107 regulated.
authors.affiliation: Institute of Genomics and Integrative Biology, Mall Road, Delhi-110 007, India.
authors.forename: Karamjit S
authors.initials: KS
authors.lastname: Dolt
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Mishra
authors.forename: Jayashree
authors.initials: J
authors.lastname: Karar
authors.forename: Masroor A
authors.initials: MA
authors.lastname: Baig
authors.forename: Zakwan
authors.initials: Z
authors.lastname: Ahmed
authors.forename: M A Qadar
authors.initials: MA
authors.lastname: Pasha
mesh_terms: D000531:Altitude; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000096:biosynthesis* / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism
chemical_list: D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger