Hormonal regulation of mitochondrial Tim23 gene expression in the mouse mammary gland.
Tim23, a mitochondrial inner membrane protein, is essential for cell viability. Mouse Tim23 cDNA consisted of 1142 nucleotides plus poly(A) at the 3' end. In situ hybridization showed that mammary epithelial cells expressed Tim23 mRNA during pregnancy. In order to examine the hormonal regulation of the Tim23 gene expression at lactogenesis, the quantity of Tim23 mRNA in the mammary gland was determined by the competitive RT-PCR. The level of Tim23 mRNA was low until mid-pregnancy, increased toward the end of pregnancy and was the highest on day 18 of pregnancy. On day 13 of pregnancy, Tim23 mRNA increased 2.7-fold between 8 and 16 h after ovariectomy but this increase was cancelled out by the simultaneous operation of adrenalectomy. In adreno-ovariectomized mice, the administration of cortisol increased Tim23 mRNA 2-fold but with progesterone, the stimulatory action of cortisol was no longer observed. The results indicated that the expression of the Tim23 gene became active in response to glucocorticoid.
Sun
Y
Y
Department of Animal Breeding, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, 113-8657, Tokyo, Japan.
Kuraishi
T
T
Aoki
F
F
Sakai
S
S
D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D006728:Hormones / Q000494:pharmacology*; D006854:Hydrocortisone / Q000494:pharmacology; D007774:Lactation; D008321:Mammary Glands, Animal / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D008813:Mice, Inbred ICR / Q000235:genetics*; D008928:Mitochondria / Q000737:chemistry; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D008969:Molecular Sequence Data; D010052:Ovariectomy; D011247:Pregnancy; D011374:Progesterone / Q000494:pharmacology; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics*
D018797:Cell Cycle Proteins; D006728:Hormones; D008565:Membrane Proteins; D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D012333:RNA, Messenger; C433865:Timm23 protein, mouse; D014157:Transcription Factors; D011374:Progesterone; D006854:Hydrocortisone