Abstract
We have isolated a gene encoding a 70,000-Da heat shock protein (HSP70) from a chicken genomic library. The recombinant clone C411 was isolated by hybridization to a radioactively labeled plasmid containing Drosophila HSP70 gene sequences. The identity was established by hybrid selected translation using a subcloned restriction fragment, pC1.8, and total cytoplasmic RNA from chicken cells. The selected mRNA translated in vitro a product which co-migrates with in vivo synthesized chicken HSP70 by SDS-polyacrylamide gel electrophoresis. By Northern blot analysis of poly(A)+ mRNA from heat-shocked cells, we detected a 2.6-kilobase pair mRNA homologous to pC1.8. The nucleotide sequences within pC1.8 and a flanking 2.0-kilobase pair HindIII fragment contain a single contiguous open reading frame of 1905 nucleotides that corresponds to a protein of predicted size 70,000 daltons. Upstream of the initiator methionine codon, ATG, lie sequences homologous to the canonical transcription elements TATA, CCAAT, and SP1 binding site, and two overlapping heat shock elements. The order and spacing of these sequences share many features in common with the promoter for the human HSP70 gene.
Highlights
We have isolated agene encoding a70,000-Da heat One of thefirst demonstrations that higher eukaryotes shockprotein (HSP70) fromachickengenomic li- exhibit a stress response similar to Drosophila was observed brary
Isolation of the Chicken HSP70 Gene-The high level of nucleotide sequence conservation shared among HSP70 genes
We detected a single DNA fragment in each digest that hybridized to pC1.8 DNA which suggested that the chicken HSP70 gene is presentas a single copy per haploid genome (Fig.8).The remote possibility that theHSP7O gene is embedded in a repeated segment that is conserved in restriction enzyme sites seems unlikely based on the relative intensity of copy equivalent DNA markers and from hybridization of the sequences in subclone pC3.8 or the entire C411 clone to XbaI, BglII, BamHI, and EcoRI digests of chicken embryo DNA
Summary
General-DNA was prepared from day 12 chicken embryos using a modifiedprotocol of Wigler et al [20]. Recombinant phage (5 X 10’) containing chicken DNA preferential synthesis of a small family of “heat shock” proteins. The synthesis of many of these proteinsis induced by exposure to amino acid analogs or metabolic inhibitors and by infection with certain DNA tumor viruses [1, 2]. Recombinant phage containing HSP70 gene-related sequences were plaque-purithis response was first identified in Drosophila cells, it has fied, and DNA wasisolated from CsCl gradient-purified phage partisince been observed in all organisms studied from bacterial, cles [23]. The nucleotide sequence(s)reported in thispaper has been submitted to the GenBankTM/EMBLData Bank with accessionnumber 502579
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
