Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.3.1.28 (
chloramphenicol acetyltransferase
)
5,100
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Phosphoglycerate kinase (PGK), a glycolytic enzyme, possesses two isozymes: somatic-type PGK-1 and testis-specific
PGK-2
, encoded by distinct genes. Tissue-specific expression of the two PGK-encoding genes (Pgk) seems to be transcriptionally controlled, since tissue distribution of the mRNAs coincides well with that of the proteins. In the present study, we determined the cis-acting DNA elements that regulate the transcription of mouse Pgk-2. A transient expression assay of DNAs having various portions of the Pgk-2 upstream region linked to the
chloramphenicol acetyltransferase
(
CAT
)-encoding gene (cat) was performed using mouse cell lines that exclusively express Pgk-1. A substantial increase in cat expression was observed when the region between nucleotides (nt) -1404 and -685, relative to the most distal transcription start point at nt +1, was lost. This cis-acting region appeared to function as a silencer, since it repressed cat expression independently of either orientation to or distance from the Pgk-2 promoter. Moreover, the cis element inhibited Pgk-2 transcription with no effect on Pgk-1 transcription in a cell-free system using nuclear extracts of rat liver. These results suggest that a silencer-like negative cis element is responsible, at least partly, for tissue-specific transcription of Pgk-2.
...
PMID:A silencer-like cis element for the testis-specific phosphoglycerate-kinase-2-encoding gene. 139 12
The gene encoding testis-specific
phosphoglycerate kinase 2
(PGK; ATP:3-phospho-D-glycerate 1-phosphotransferase, EC 2.7.2.3) is expressed only in meiotic and haploid male germ cells. Transgenic mice containing an 8-kilobase human genomic
PGK2
gene express the human gene in a tissue-specific and developmentally regulated manner. To determine the nature and location of sequences controlling this expression, transgenic mice with various lengths of the human
PGK2
5' region fused to the
chloramphenicol acetyltransferase
(
CAT
) gene were analyzed for expression. A 323-base-pair region 5' to the coding region was found to contain information essential for both tissue-specific and developmentally regulated expression of the
CAT
reporter gene. Transgenic mice containing a
PGK2
/luciferase-coding construct were compared with mice containing an equivalent
CAT
construct. Luciferase gene expression was also testis-specific and was more sensitive than
CAT
gene expression, but otherwise regulation of the two reporter genes was similar in the germ cells of transgenic mice. Translation of both
PGK2
/
CAT
and
PGK2
/luciferase fusion genes was seen concurrently with the first detectable transcripts.
...
PMID:Transcriptional regulatory regions of testis-specific PGK2 defined in transgenic mice. 281 2
The
PGK2
gene is expressed in a strictly tissue-specific manner in meiotic spermatocytes and postmeiotic spermatids during spermatogenesis in eutherian mammals. Previous results indicate that this is regulated at the transcriptional level by core promoter sequences that bind ubiquitous transcription factors and by sequences in a 40-base pair (bp) upstream enhancer region (E1/E4) that bind tissue-specific transcription factors. Transgenic mice carrying different
PGK2
promoter sequences linked to the
chloramphenicol acetyltransferase
(
CAT
) reporter gene, one containing only the 40-bp E1/E4 enhancer sequence plus the core promoter and two containing 515 bp of
PGK2
promoter but with either the E1/E4 enhancer region or the Sp1-binding site in the core promoter disrupted by in vitro mutagenesis, all showed levels of expression reduced to less than half that of the wild-type 515
PGK2
/
CAT
transgene. These results indicate that multiple factor-binding regions normally regulate initiation of transcription from the
PGK2
promoter. The single disruption of any one of these binding activities reduced, but did not abolish, transgene expression. This is consistent with an "enhanceosome"-like function in this promoter involving multiple bound activator proteins that interact in a combinatorial manner to synergistically promote testis-specific transcription.
...
PMID:Multiple elements influence transcriptional regulation from the human testis-specific PGK2 promoter in transgenic mice. 1033 89
In Trypanosoma brucei, the
PGKB
and PGKC genes-encoding phosphoglycerate kinase are co-transcribed as part of a polycistronic RNA.
PGKB
mRNA and the cytosolic
PGKB
protein are much more abundant in the procyclic life-cycle stage than in bloodstream forms, whereas PGKC mRNA and glycosomal PGKC protein are specific to bloodstream forms. We here show that a sequence between nucleotides 558 and 779 in the 3'-untranslated region of the PGKC mRNA causes low expression of the
chloramphenicol acetyltransferase
(
CAT
) reporter gene in procyclic trypanosomes. In procyclics, depletion of the RRP45 component of the exosome (3'-->5' exonuclease complex) or the 5'-->3' exonuclease XRNA increased the abundance of
CAT
-PGKC mRNA as a consequence of effects on the degradation of precursor and/or mature mRNAs. In bloodstream forms, inhibition of both trans splicing and transcription resulted in immediate exponential decay of PGKC mRNA with a half-life of 46 min. Inhibition of transcription alone gave non-exponential kinetics and inhibition of splicing alone resulted in a longer apparent half-life. We also found that production of mRNAs using T7 polymerase can affect the apparent half-life, and that large amounts of
CAT
enzyme may be toxic in trypanosomes.
...
PMID:Regulated expression of glycosomal phosphoglycerate kinase in Trypanosoma brucei. 1718 72