Alternative promoter and GATA5 transcripts in mouse.
GATA5 is a member of the GATA zinc finger transcription factor family involved in tissue-specific transcriptional regulation during cell differentiation and embryogenesis. Previous reports indicate that null mutation of the zebrafish GATA5 gene results in embryonic lethality, whereas deletion of exon 1 from the mouse GATA5 gene causes only derangement of female urogenital development. Here, we have identified an alternate promoter within intron 1 of the mouse GATA5 gene that transcribes a 2.5-kb mRNA that lacks exon 1 entirely but includes 82 bp from intron 1 and all of exons 2-6. The alternative promoter was active during transient transfection in cultured airway myocytes and bronchial epithelial cells, and it drove reporter gene expression in gastric epithelial cells in transgenic mice. The 2.5-kb alternative transcript encodes an NH(2)-terminally truncated "short GATA5" comprising aa 226-404 with a single zinc finger, which retains ability to transactivate the atrial natriuretic factor promoter (albeit less efficiently than full-length GATA5). Another new GATA5 transcript contains all of exons 1-5 and the 5' portion of exon 6 but lacks the terminal 1143 bp of the 3'-untranslated region from exon 6. These findings extend current understanding of the tissue distribution of GATA5 expression and suggests that GATA5 expression and function are more complex than previously appreciated.
Departments of Medicine, Univ. of Chicago, IL 60637, USA.
Bohao
B
Chen
Elena
E
Yates
Yong
Y
Huang
Paul
P
Kogut
Lan
L
Ma
Jerrold R
JR
Turner
Yun
Y
Tao
Blanca
B
Camoretti-Mercado
Deborah
D
Lang
Eric C
EC
Svensson
Joe G N
JG
Garcia
Peter J
PJ
Gruber
Edward E
EE
Morrisey
Julian
J
Solway
D020413:3' Untranslated Regions; D024506:5' Flanking Region; D017398:Alternative Splicing; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000235:genetics / Q000378:metabolism; D015152:Blotting, Northern; D004285:Dogs; D004847:Epithelial Cells / Q000378:metabolism; D005091:Exons; D050992:GATA5 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism; D017930:Genes, Reporter; D007438:Introns; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D032389:Myocytes, Smooth Muscle / Q000378:metabolism; D041681:NIH 3T3 Cells; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism*; D019105:Random Amplified Polymorphic DNA Technique; D020545:Respiratory Mucosa / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D024363:Transcription Initiation Site; D015533:Transcriptional Activation; D014162:Transfection
D020413:3' Untranslated Regions; D050992:GATA5 Transcription Factor; C494756:Gata5 protein, mouse; D020033:Protein Isoforms; D012333:RNA, Messenger; D009320:Atrial Natriuretic Factor