Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In soybean, the small heat shock proteins of 15 to 18 kDa are encoded in the nucleus by at least two different multigene families, designated class I and class VI. Genomic DNA sequences of two new heat shock genes and flanking regions were determined: Gmhsp18.5-C, a class I gene, and Gmhsp17.9-D, the first known class VI gene. Comparison of both genes revealed a moderate homology (approx. 38%) mainly within the 3' ends of their coding regions. Hydropathic characterizations and secondary-structure predictions of the deduced amino acid sequences revealed two conserved domains within the C-terminal halves of the polypeptides that are also present in related proteins of other organisms. The transcription of both genes is heat shock dependent and the mRNA start sites, as determined by S1 nuclease mapping, are located downstream from typical TATA box sequences and multiple heat shock promoter elements such as 5' CT-GAA--TTC-AG. The putative promoter regions of the genes are preceded by long tracts of repetitive sequences with a high A + T content of 79 to 89%, which are bordered by runs of "simple sequences" such as (A) 12/13, (T)10 and (TA)10. Similar characteristic features are present in the promoter and 5'-flanking regions of other soybean heat shock genes. The possible function of these distinct sequences is discussed.
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PMID:Nucleotide sequence analysis of soybean small heat shock protein genes belonging to two different multigene families. 335 43

A 359 bp terminal exon fragment of the rat polymeric immunoglobulin receptor gene has been tested for biological effects. The fragment contains an S1 nuclease-sensitive microsatellite with d(GGA) and d(GAA) trinucleotide repeats that are expressed discordantly in the 3'UTRs of liver mRNAs encoded by the single copy gene. When human A293 cells are transfected with expression plasmids carrying this fragment in forward orientations, flanking or replacing poly(A) cassettes in the 3' ends of the transcription units, luciferase reporter gene expression is attenuated 47 to 59% or 98.5%, respectively. In contrast, when the fragment is tested similarly in reverse orientation, there is significantly less or no attenuation of gene expression. These observations, and computer models of partial triplet repeat DNA tertiary and RNA secondary structures, suggest that this fragment might regulate gene expression by orientation and position-dependent mechanisms at transcriptional and post-transcriptional levels.
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PMID:Attenuation of gene expression by a trinucleotide repeat-rich tract from the terminal exon of the rat hepatic polymeric immunoglobulin receptor gene. 909 21

The soybean possesses a gene family encoding the major low mol. wt. heat-shock proteins of 15-18 kd. We have determined the primary DNA sequences of two of the genes, both located on the same subgenomic DNA fragment. The protein coding regions are characterized by long uninterrupted open reading frames and by sequence homology of 92% and 100% with a heat-shock specific cDNA. One protein sequence deduced from the completely cloned gene hs6871 is composed of 153 amino acids with a total mol. wt. of 17.3 kd; the other protein is a truncated polypeptide containing 73 amino acids at the carboxy-terminal end of an incompletely cloned heat-shock gene designated hs6834. Investigations of the hydrophilic/hydrophobic characteristics of the polypeptides revealed a conservation of structural features between heat-shock proteins from soybean, Caenorhabditis and Drosophila and mammalian lens alpha-crystallin. The 5' end of the soybean heat-shock gene hs6871 was mapped by S1 nuclease at a position which is 100 nucleotides upstream from the translation start codon and 25 nucleotides downstream from a TATA-box sequence. Six other potential promoter elements which are homologous to the Drosophila heat-shock consensus sequence CT-GAA-TTC-AG-, are present within 150 nucleotides upstream from the TATA-box. The possible functions of these promoter elements in transcriptional regulation of expression of soybean heat-shock gene are discussed.
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PMID:The DNA sequence analysis of soybean heat-shock genes and identification of possible regulatory promoter elements. 1645 63