Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.3.1.28 (chloramphenicol acetyltransferase)
 5,100 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A murine mesangial cell line (MMC) was established from the glomeruli of SJL mice to study the influence of angiotensin II (ANG II) on their growth and function in a serum-free culture. Murine mesangial cells exhibit the phenotypic characteristics of mesangial cells, including staining for desmin, vimentin, Thy 1, and types I and IV collagen by immunofluorescence. The addition of daily doses of 10(-6) to 10(-11) mol/l ANG II to MMCs also induced their proliferation in serum-free media. This effect on growth was independent of the presence of insulin in the media, and was receptor mediated, because the specific ANG II-receptor antagonist DuP 753 abolished proliferative growth. Angiotensin II also stimulated mainly the biosynthesis of type I collagen in our MMCs. Transfection of MMCs with chimeric genes containing enhancer/promoter elements for alpha 2(I) and alpha 1(IV) collagens linked to a chloramphenicol acetyltransferase reporter demonstrated that the stimulatory effect of ANG II for type I depends, at least to some extent, on an increase in transcription. These findings indicate collectively that ANG II in serum-free cultures can be a paracrine catalyst for the growth and biosynthesis of type I collagen in mesangial cells.
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PMID:Angiotensin II stimulates the proliferation and biosynthesis of type I collagen in cultured murine mesangial cells. 173 33

We assessed the effect of angiotensin II on fibronectin biosynthesis a nd transcription factor activation in adult human mesangial cells in culture. We found that 10(-5) mol/L angiotensin II tended to increase fibronectin mRNA expression within 1 hour (1.2-fold +/- 0.3-fold of that in controls), with a significant increase after 4 hours (0.3-fold +/- 0.1-fold of that in controls, p < 0.05) and 24 hours (1.9-fold +/- 0.3-fold of that in controls, p < 0.02). In conjunction with increased fibronectin mRNA levels, angiotensin II exposure resulted in a significant elevation in immunoreactive fibronectin concentrations and the incorporation of (35S)-labeled methionine into fibronectin after 2 hours (224% +/- 23% of controls, p < 0.05). Angiotensin II also induced mesangial cell activation of the cyclic adenosine monophosphate response element binding protein (CREB) transcription factor, a DNA binding protein known to recognize specific regulatory elements present on the fibronectin gene promoter. Using the electrophoretic mobility shift assay, we showed that angiotensin II increased mesangial cell expression of the activated form of CREB after 4 hours (1.2-fold +/- 0.04-fold of that in controls, p < 0.05). To determine the importance of the CREB regulatory elements in mediating angiotensin II induction of fibronectin gene transcription, JEG-3 cells were transfected with plasmids containing fibronectin promoter-chloramphenicol acetyltransferase (CAT) reporter gene constructs with (FN510) or without (FN122) the CREB regulatory motifs. Angiotensin II resulted in a significant increase in CAT activity in FN510 transfectants (1.6-fold +/- 0.2-fold of that in controls, p < 0.05), but there was no effect of angiotensin II on FN122 transfected cells. These data demonstrate that angiotensin II stimulates fibronectin biosynthesis in adult human mesangial cells and suggest that the process may be regulated at the transcriptional level.
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PMID:Angiotensin II induction of fibronectin biosynthesis in cultured human mesangial cells: association with CREB transcription factor activation. 864 65