title: Alternate Pax7 transcripts are expressed specifically in skeletal muscle, brain and other organs of adult mice.
abstract: Pax7 is associated with formation of skeletal muscle and the neural tube in developing embryos. Interestingly, in adult mice, rearrangements of Pax7 are associated with differences in the efficiency of skeletal muscle regrowth between mouse strains. The aim of this study was to investigate the possibility that Pax7 is expressed in skeletal muscle or other tissues from adult mice. Total RNA was isolated from adult mouse tissues and the polymerase chain reaction was performed on reverse transcribed mRNA using primers specific for regions that encode the paired and homeodomain of Pax7. At least four different Pax7 transcripts were found. A full-length transcript similar in sequence to that published previously was identified in skeletal muscle, brain and spleen cells of adult mice. Further putative full-length Pax7 transcripts, including one that contains a hexanucleotide insertion in the paired box and one in which approximately 10 bp have been deleted in the homeobox, were found to be expressed in skeletal muscle and brain of adult mice, respectively. A truncated Pax7 splice product comprising the paired box only was found to be expressed in most adult tissues except liver. Results of these studies demonstrate that there are alternate transcripts of Pax7, some of which are expressed exclusively in adult skeletal muscle and brain. It is possible that one of these transcripts may specify an alternate myogenic pathway involved in regeneration of damaged skeletal muscle in adult mice.
authors.affiliation: Department of Pathology, University of Western Australia, Nedlands, Australia.
authors.forename: M R
authors.initials: MR
authors.lastname: Ziman
authors.forename: S
authors.initials: S
authors.lastname: Fletcher
authors.forename: P H
authors.initials: PH
authors.lastname: Kay
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D001921:Brain / Q000254:growth & development / Q000378:metabolism*; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D024510:Muscle Development; D009124:Muscle Proteins / Q000096:biosynthesis / Q000235:genetics*; D018482:Muscle, Skeletal / Q000254:growth & development / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics*; D009928:Organ Specificity; D051763:PAX7 Transcription Factor; D016133:Polymerase Chain Reaction; D012322:RNA Precursors / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D018398:Homeodomain Proteins; D009124:Muscle Proteins; D009419:Nerve Tissue Proteins; D051763:PAX7 Transcription Factor; C497322:Pax7 protein, mouse; D012322:RNA Precursors; D012333:RNA, Messenger