Androgens transcriptionally regulate the expression of cystatin-related protein and the C3 component of prostatic binding protein in rat ventral prostate and lacrimal gland.
In this report, it is demonstrated that the C3 component of prostatic binding protein (PBP) is also expressed and androgen regulated in the exorbital lacrimal gland, as shown previously for cystatin-related protein (CRP), another abundant secretory protein from the ventral prostate. The presence of C3 messenger RNA (mRNA) could be demonstrated by both Northern blot hybridization and PCR amplification and sequencing. The mRNAs encoding the C1 and C2 components of PBP, however, were undetectable. At the protein level, the C3 component in the lacrimal gland is glycosylated and linked by disulfide bridges to a new 10-kDa component not reacting with the PBP antiserum. As shown previously for CRP, the expression of C3 in the lacrimal gland requires the simultaneous presence of androgens and a functional androgen receptor. The effects of castration and androgen treatment on CRP and C3 mRNA concentrations were studied by Northern blot and dot blot hybridization; effects on transcription rates were determined by nuclear run-on assay. Two days after castration, the relative abundance of CRP mRNA had declined significantly (P < 0.01) to 10.5 +/- 1.5% (+/-SEM) of precastration levels in the prostate and to 14.5 +/- 8.0% in the lacrimal gland; the transcription rates declined to 14.3% and 10.0%, respectively. The C3 mRNA level and transcription rate in the prostate showed a more moderate decrease (P < 0.05) to 40.6 +/- 8.5% and 41.7%, but were hardly measurable in the lacrimal gland. Androgen administration resulted in a rapid increase in the transcription rates, which reached or exceeded control levels after 6-9 h of treatment and clearly preceded the increase in mRNA levels. It is concluded that the lacrimal gland, which can be studied conveniently in female and long term androgen-depleted animals offers a suitable model for the study of androgen-regulated gene expression.
Laboratory for Experimental Medicine and Endocrinology, Onderwijs en Navorsing, Gasthuisberg, Leuven, Belgium.
I
I
Vercaeren
H
H
Vanaken
A
A
Devos
B
B
Peeters
G
G
Verhoeven
W
W
Heyns
D000704:Analysis of Variance; D000727:Androgen-Binding Protein / Q000096:biosynthesis* / Q000302:isolation & purification; D000728:Androgens / Q000494:pharmacology*; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002467:Cell Nucleus / Q000378:metabolism; D015891:Cystatins; D017931:DNA Primers; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D007700:Kinetics; D007765:Lacrimal Apparatus / Q000378:metabolism*; D008297:Male; D009919:Orchiectomy; D016133:Polymerase Chain Reaction; D011467:Prostate / Q000187:drug effects / Q000378:metabolism*; D060789:Prostatein; D014176:Protein Biosynthesis; D011506:Proteins; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D060765:Secretoglobins; D014158:Transcription, Genetic / Q000187:drug effects; D014598:Uteroglobin; D060788:Mammaglobin B
D000727:Androgen-Binding Protein; D000728:Androgens; D015891:Cystatins; D017931:DNA Primers; D060789:Prostatein; D011506:Proteins; D012333:RNA, Messenger; D060765:Secretoglobins; D014598:Uteroglobin; C079958:Andpro protein, rat; C484121:P22k15 protein, rat; C511484:Scgb1d2 protein, rat; C511483:Scgb1d4 protein, rat; C556468:Scgb2a1 protein, rat; D060788:Mammaglobin B