A novel mouse protein differentially regulated by androgens in the submandibular and lacrimal glands.
We characterized a cDNA clone derived from the female mouse submandibular gland (SMG). The transcript of this cDNA was approximately 1.2kb in size and predicted to code a 165-amino acid protein with a putative signal peptide for a secretory pathway. This protein, named submandibular androgen-repressed protein (SMARP), had homology in the N-terminal region with members of the glutamine/glutamic acid-rich protein (GRP) family from rats. Northern blot analysis revealed that SMARP mRNA is expressed, out of the major mouse organs, only in the SMG and exorbital lacrimal gland (LG), with much more abundance in the former. For the SMG, the level of SMARP mRNA was 36 times higher in females than males, whereas for the LG it was 28 times higher in males than females. Furthermore, the level of SMARP mRNA was increased in the SMG but reduced in the LG with castration in males, whereas it was reduced in SMG but increased in LG after administration of testosterone in females or castrated males. In situ hybridization detected the signal for SMARP mRNA in the female SMG, and immunohistochemistry detected the signal for SMARP protein in the female SMG and male LG. In the female SMG, SMARP mRNA, and protein were localized intensively in a subpopulation of acinar cells, whereas in the male LG, SMARP protein was distributed diffusely in all acinar cells. These results suggested that SMARP is a secretory protein whose expression is regulated by androgens negatively in the SMG and positively in the LG.
Sakulsak
Natthiya
N
Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
Wakayama
Tomohiko
T
Hipkaeo
Wiphawi
W
Iseki
Shoichi
S
D000728:Androgens / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D015536:Down-Regulation; D005260:Female; D018698:Glutamic Acid / Q000032:analysis; D005973:Glutamine / Q000032:analysis; D007765:Lacrimal Apparatus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009919:Orchiectomy; D010052:Ovariectomy; D011392:Proline / Q000032:analysis; D021382:Protein Sorting Signals / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D012471:Salivary Proteins and Peptides / Q000032:analysis / Q000187:drug effects / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D012727:Sex Characteristics; D013363:Submandibular Gland / Q000187:drug effects / Q000378:metabolism*; D013739:Testosterone / Q000494:pharmacology; D015854:Up-Regulation
D000728:Androgens; D021382:Protein Sorting Signals; D012333:RNA, Messenger; D012471:Salivary Proteins and Peptides; C525244:submandibular androgen-repressed protein, mouse; D005973:Glutamine; D018698:Glutamic Acid; D013739:Testosterone; D011392:Proline