Analysis of tyrosine hydroxylase and insulin transcripts in human neuroendocrine tissues.
We have previously shown that the mRNA for human tyrosine hydroxylase (TH) exists in one of 4 forms as a result of alternative splicing of intron 1. In order to determine the tissue-specific expression of the multiple human transcripts we have utilized specifically primed polymerase chain reactions (PCR) in combination with reverse-transcribed RNA. Using PCR analysis we determined that many human neuronal tissues express all 4 forms of human TH (hTH-1-4); however, hTH-3 and -4 are generally expressed at less than 1% of the other two. Of all tissues examined, only pancreatic beta-islet cells expressed a single form of human TH mRNA (hTH-2). The mRNA for rat TH is present in only one form, the equivalent of hTH-1. Since we have shown that the human genes for TH and insulin are only 2.7 kb apart and several groups have reported insulin-like expression in neuronal tissues, we looked for insulin transcription in the same central and peripheral nervous system samples. Insulin mRNA was not present within the limits of detection.
Coker
G T
GT
Department of Anatomy and Neurobiology, Washington University Medical School, St. Louis, MO 63110.
Studelska
D
D
Harmon
S
S
Burke
W
W
O'Malley
K L
KL
D000818:Animals; D001483:Base Sequence; D004790:Enzyme Induction; D005091:Exons; D005786:Gene Expression Regulation; D005796:Genes; D006801:Humans; D007328:Insulin / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D009490:Neurosecretory Systems / Q000378:metabolism*; D015345:Oligonucleotide Probes; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D012326:RNA Splicing / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D014446:Tyrosine 3-Monooxygenase / Q000096:biosynthesis* / Q000235:genetics
D007328:Insulin; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D014446:Tyrosine 3-Monooxygenase