BIOLOGIC AND BIOCHEMICAL EFFECTS OF ANTI-ANDROGENS ON RAT VENTRAL PROSTATE

1974 ◽  
Vol 75 (2) ◽  
pp. 385-397 ◽  
Author(s):  
Jack Geller ◽  
Kevin McCoy
Keyword(s):  
Complex Formation ◽  
Protein Complex ◽  
Ventral Prostate ◽  
Common Denominator ◽  
Biochemical Effects ◽  
Protein Complex Formation ◽  
Biologic Effects ◽  
Rat Prostate

ABSTRACT To determine whether the similarity of biologic effects of two antiandrogens, cyproterone acetate (Cyp A) and edogesterone (PH-218), could be related to one or more common biochemical effects, we have compared the effects of both drugs on 3H testosterone (3HT) entry into cells, binding to specific cytosol and nuclear androphiles, and conversion to dihydrotestosterone (DHT). In chronic in vivo studies, both Cyp A and PH-218 reduced rat prostate weights by approximately 50% and specific cytosol steroid-protein complex formation by approximately 60 %. At the same time, Cyp A decreased the formation of nuclear steroid-protein complex to 10% of control values, compared with 40% for PH-218. In addition, Cyp A, but not PH-218, significantly decreased total 3HT uptake by the prostate. Similar effects of Cyp A on 3HT uptake, binding, and metabolism were noted in acute in vivo and in vitro experiments. PH-218 effects on these same parameters were reduced in acute, compared to chronic, studies. Neither drug significantly affected the conversion of T to DHT. Despite quantitative differences between Cyp A and PH-218, these studies support the concept that the biochemical common denominator for the biologic effects of anti-androgens is inhibition of specific steroid-protein complex formation in both cytosol and nucleus.

scholarly journals Mutational Analysis of the Rhizobium etli recA Operator

1998 ◽  
Vol 180 (23) ◽  
pp. 6325-6331 ◽  
Author(s):  
Angels Tapias ◽  
Jordi Barbé
Keyword(s):  
Complex Formation ◽  
Protein Complex ◽  
Mutational Analysis ◽  
Rhizobium Meliloti ◽  
Regulatory Sequence ◽  
Rhizobium Etli ◽  
Wild Type ◽  
Protein Complex Formation

ABSTRACT Based upon our earlier studies (A. Tapias, A. R. Fernández de Henestrosa, and J. Barbé, J. Bacteriol. 179:1573–1579, 1997) we hypothesized that the regulatory sequence of the Rhizobium etli recA gene was TTGN11CAA. However, further detailed analysis of the R. etli recAoperator described in the present work suggests that it may in fact be GAACN7GTAC. This new conclusion is based upon PCR mutagenesis analysis carried out in the R. etli recAoperator, which indicates that the GAAC and GTAC submotifs found in the sequence GAACN7GTAC are required for the maximal stimulation of in vivo transcription and in vitro DNA-protein complex formation. This DNA-protein complex is also detected when the GAACN7GTAC wild-type sequence is modified to obtain GAACN7GAAC, GTACN7GTAC, or GAACN7GTTC. The wild-type promoters of the Rhizobium meliloti and Agrobacterium tumefaciens recA genes, which also contain the GAACN7GTAC sequence, compete with the R. etli recA promoter for the DNA-protein complex formation but not with mutant derivatives in any of these motifs, indicating that the R. etli, R. meliloti, andA. tumefaciens recA genes present the same regulatory sequence.

THE BINDING OF [1,2-3H]TESTOSTERONE WITHIN NUCLEI OF THE RAT PROSTATE

1969 ◽  
Vol 44 (3) ◽  
pp. 323-333 ◽  
Author(s):  
W. I. P. MAINWARING
Keyword(s):  
Molecular Weight ◽  
Equilibrium Dialysis ◽  
Prostate Gland ◽  
Ventral Prostate ◽  
Rat Tissues ◽  
Receptor Complex ◽  
Rat Prostate ◽  
Binding Component

SUMMARY The specificity of the binding of [1,2-3H]testosterone to nuclei of various rat tissues in vivo has been studied. A significant amount of radioactivity was retained in the nuclei of androgen-dependent tissues only, particularly the ventral prostate gland. The bound radioactivity was only partially recovered as [1,2-3H]testosterone; the remainder was identified as [3H]5α-dihydrotestosterone. Efforts were made to characterize the binding component, or 'receptor', in prostatic nuclei. On digestion of nuclei labelled in vivo with [1,2-3H]testosterone, with enzymes of narrow substrate specificity, only trypsin released tritium, suggesting that the receptor is a protein. On the basis of subfractionation studies of labelled nuclei, the receptor is an acidic protein. The androgen—receptor complex could be effectively extracted from the prostatic nuclei in 1 m-NaCl and from the results of fractionations on a calibrated agarose column, the complex has a molecular weight 100,000–120,000. The specificity of the binding of steroids to such 1 m-NaCl extracts in vitro was investigated by the equilibrium dialysis procedure. Under these conditions, the specificity of the binding of [1,2-3H]testosterone demonstrated in vivo could not be simulated. The receptor is probably part of the chromatin complex but its precise intranuclear localization cannot be determined by biochemical procedures alone.

Novel Procedure To Investigate the Effect of Phosphorylation on Protein Complex Formation in Vitro and in Cells†

Biochemistry ◽  
2008 ◽  
Vol 47 (7) ◽  
pp. 2153-2161 ◽  
Author(s):  
Makoto Rembutsu ◽  
Marc P. M. Soutar ◽  
Lidy Van Aalten ◽  
Robert Gourlay ◽  
C. James Hastie ◽  
...  
Keyword(s):  
Complex Formation ◽  
Protein Complex ◽  
Protein Complex Formation ◽  
In Cells

scholarly journals Robust assessment of protein complex formation in vivo via single-molecule intensity distributions of autofluorescent proteins

2011 ◽  
Vol 16 (7) ◽  
pp. 076016 ◽  
Author(s):  
Tobias Meckel ◽  
Stefan Semrau ◽  
Marcel J. M. Schaaf ◽  
Thomas Schmidt
Keyword(s):  
Complex Formation ◽  
Single Molecule ◽  
Protein Complex ◽  
Protein Complex Formation

scholarly journals Unstructured mRNAs form multivalent RNA-RNA interactions to generate TIS granule networks

2020 ◽  
Author(s):  
Weirui Ma ◽  
Gang Zhen ◽  
Wei Xie ◽  
Christine Mayr
Keyword(s):  
Endoplasmic Reticulum ◽  
Protein Synthesis ◽  
Complex Formation ◽  
Major Site ◽  
Intrinsically Disordered ◽  
Intrinsically Disordered Regions ◽  
Protein Complex Formation ◽  
Unstructured Regions

SummaryThe TIS granule network is a constitutively expressed membraneless organelle that concentrates mRNAs with AU-rich elements and interacts with the major site of protein synthesis, the rough endoplasmic reticulum. Most known biomolecular condensates are sphere-like, but TIS granules have a mesh-like morphology. Through in vivo and in vitro reconstitution experiments we discovered that this shape is generated by extensive intermolecular RNA-RNA interactions. They are mostly accomplished by mRNAs with large unstructured regions in their 3′UTRs that we call intrinsically disordered regions (IDRs). As AU-rich RNA is a potent chaperone that suppresses protein aggregation and is overrepresented in mRNAs with IDRs, our data suggests that TIS granules concentrate mRNAs that assist protein folding. In addition, the proximity of translating mRNAs in TIS granule networks may enable co-translational protein complex formation.

scholarly journals An AU-rich element in the 3' untranslated region of the spinach chloroplast petD gene participates in sequence-specific RNA-protein complex formation.

1995 ◽  
Vol 15 (4) ◽  
pp. 2010-2018 ◽  
Author(s):  
Q Chen ◽  
C C Adams ◽  
L Usack ◽  
J Yang ◽  
R A Monde ◽  
...  
Keyword(s):  
Complex Formation ◽  
Protein Complex ◽  
Untranslated Region ◽  
Rna Binding ◽  
Rbcl Gene ◽  
Spinach Chloroplast ◽  
Protein Complex Formation ◽  
Sequence Elements ◽  
Chloroplast Mrna

In chloroplasts, the 3' untranslated regions of most mRNAs contain a stem-loop-forming inverted repeat (IR) sequence that is required for mRNA stability and correct 3'-end formation. The IR regions of several mRNAs are also known to bind chloroplast proteins, as judged from in vitro gel mobility shift and UV cross-linking assays, and these RNA-protein interactions may be involved in the regulation of chloroplast mRNA processing and/or stability. Here we describe in detail the RNA and protein components that are involved in 3' IR-containing RNA (3' IR-RNA)-protein complex formation for the spinach chloroplast petD gene, which encodes subunit IV of the cytochrome b6/f complex. We show that the complex contains 55-, 41-, and 29-kDa RNA-binding proteins (ribonucleoproteins [RNPs]). These proteins together protect a 90-nucleotide segment of RNA from RNase T1 digestion; this RNA contains the IR and downstream flanking sequences. Competition experiments using 3' IR-RNAs from the psbA or rbcL gene demonstrate that the RNPs have a strong specificity for the petD sequence. Site-directed mutagenesis was carried out to define the RNA sequence elements required for complex formation. These studies identified an 8-nucleotide AU-rich sequence downstream of the IR; mutations within this sequence had moderate to severe effects on RNA-protein complex formation. Although other similar sequences are present in the petD 3' untranslated region, only a single copy, which we have termed box II, appears to be essential for in vitro protein binding. In addition, the IR itself is necessary for optimal complex formation. These two sequence elements together with an RNP complex may direct correct 3'-end processing and/or influence the stability of petD mRNA in chloroplasts.

Sign in / Sign up

Export Citation Format

Share Document