Sequence analysis and androgen regulation of MHG07 (Male harderian gland) mRNA in male hamster harderian gland.
The hamster Harderian gland (HG), a compound tubuloalveolar gland located in the orbital cavity, displays sex dimorphism. The present study focuses on the sequence analysis of a cDNA clone named MHG07 and on the regulation of its expression by steroid hormones. MHG07 mRNA (5.0 kb) is expressed in male HG only. The MHG07 cDNA (1.74 kb) shows an ORF of 94 amino acids and has no significant homologies with other polypeptides/genes. Castration leads to the disappearance of MHG07 mRNA after 4 days, whereas treatment with testosterone impairs the effect of castration. No MHG07 mRNA has been found in either rat or murine HGs. Androgen (A) administration to female hamsters induces the appearance of MHG07 mRNA. In primary culture of male hamster HG, androgens increase the MHG07 expression and this effect is blocked by both flutamide and cycloheximide. Dose-response experiments show that, at low A concentration (10(-12) M), the MHG07 was higher than that of the control (2-fold). This effect reaches its zenith at 10(-8) M (10-fold). This picture is paralleled by androgen receptor mRNA expression. It is argued that the expression of MHG07 is under androgenic control.
Dipartimento di Fisiologia Umana e Funzioni Biologiche Integrate, II Università di Napoli, Naples, 80138, Italy.
T
T
Esposito
E
E
Astore
P
P
Dominguez
G
G
Chieffi
B
B
Varriale
D000595:Amino Acid Sequence; D000728:Androgens / Q000494:pharmacology* / Q000502:physiology; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D006224:Cricetinae; D046508:Culture Techniques; D018076:DNA, Complementary / Q000737:chemistry; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D006243:Harderian Gland / Q000737:chemistry / Q000378:metabolism*; D008297:Male; D008647:Mesocricetus; D008969:Molecular Sequence Data; D009919:Orchiectomy; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism*; D011944:Receptors, Androgen / Q000235:genetics; D017422:Sequence Analysis, DNA; D012727:Sex Characteristics; D013739:Testosterone / Q000494:pharmacology
D000728:Androgens; D018076:DNA, Complementary; D012333:RNA, Messenger; D011944:Receptors, Androgen; D013739:Testosterone