Heat shock alters poly(A) tail length of Dictyostelium discoideum hsp32 RNA.
Hsp32 is a heat shock gene in D. discoideum. We have previously observed that heat stress-induced change produces a broad band on Northern blots, suggesting that more than one population of mRNA is present under those conditions. This was not the result of a defect in the splicing of the hsp32 mRNA, nor did it result from the use of a different transcription start site under heat shock conditions. Here, we show that the broad banding pattern reflects the appearance of a transcript with a poly(A) tail that is approximately 100 nt longer than that seen in unstressed cells. Experiments indicated that this tail was not a property of newly synthesized mRNA but rather a response to heat stress. This response appeared to be specific to the hsp32 transcript and did not result in the retention of the RNA in the nucleus. These results document a relatively unusual heat shock response and also indicate that the nature of the response differs among RNAs and has selective consequences.
E.A. Doisy Department of Biochemistry and Molecular Biology, St. Louis University School of Medicine, MO 63104, USA.
A M
AM
Moerman
A C
AC
de Maria
S L
SL
Gomes
C
C
Klein
D000818:Animals; D003470:Culture Media / Q000494:pharmacology; D004023:Dictyostelium / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005057:Eukaryotic Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D006360:Heat-Shock Proteins / Q000187:drug effects / Q000235:genetics*; D018869:Heat-Shock Response / Q000235:genetics*; D011061:Poly A / Q000235:genetics / Q000378:metabolism*; D015800:Protozoan Proteins; D012313:RNA / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D013696:Temperature; D013997:Time Factors
D003470:Culture Media; D006360:Heat-Shock Proteins; C107554:Hsp32 protein, Dictyostelium discoideum; D015800:Protozoan Proteins; D012333:RNA, Messenger; D011061:Poly A; D012313:RNA