Regulation of ADP-ribosylation factor (ARF) expression. Cross-species conservation of the developmental and tissue-specific alternative polyadenylation of ARF 4 mRNA.
ADP-ribosylation factors (ARFs), approximately 20-kDa guanine nucleotide-binding proteins, are involved in protein trafficking and enhance cholera toxin ADP-ribosyltransferase activity. Expression of six ARF genes was examined in mammalian tissues; only ARF 4 mRNA was detected in rat testis in forms considerably shorter than those in other tissues. Testis-specific expression of short forms of ARF 4 mRNA was observed in several mammalian species. On Northern analysis of the developmental expression of rat ARF 4 mRNA, appearance of the shorter species was consistent with its involvement in a late stage of spermatogenesis. Sequences of products of rapid amplification of cDNA ends (RACE-polymerase chain reaction) of rat ARF 4 mRNA revealed that different mRNAs resulted from the use of three polyadenylation signals, one AUUAAA and two AAUAAA. Sequences of 3'-untranslated regions of rat and human ARF 4 mRNA were very similar with identical polyadenylation signals at similar positions. Of the ARF 4 mRNAs identified by RACE-PCR, with sizes of 1.1, 1.3, and 1.8 kb, the 1.1-kb mRNA was predominant in adult testis. By in situ hybridization, the 1.1-kb mRNA was identified primarily in mature sperm, consistent with the developmental studies. Shorter mRNAs, thought to be more stable, may compensate for cessation of transcription at late stages of spermatogenesis.
Laboratory of Cellular Metabolism, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892.
K
K
Mishima
S R
SR
Price
M S
MS
Nightingale
E
E
Kousvelari
J
J
Moss
M
M
Vaughan
D020727:ADP-Ribosylation Factors; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004822:Epididymis / Q000166:cytology / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D009928:Organ Specificity; D011061:Poly A / Q000235:genetics / Q000378:metabolism*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013737:Testis / Q000502:physiology
D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D011061:Poly A; D004247:DNA; D019204:GTP-Binding Proteins; D020727:ADP-Ribosylation Factors