Search Results
You are looking at 1 - 1 of 1 items for
- Author: N-S Xia x
- Refine by access: All content x
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by J Miao in
Google Scholar
PubMed
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by K-W Chan in
Google Scholar
PubMed
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by G G Chen in
Google Scholar
PubMed
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by S-Y Chun in
Google Scholar
PubMed
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by N-S Xia in
Google Scholar
PubMed
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by J Y H Chan in
Google Scholar
PubMed
Chemical Pathology, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China
Department of Biology, Xiamen University, Xiamen, People’s Republic of China
Molecular Pathology, University of Texas M D Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
Search for other papers by N S Panesar in
Google Scholar
PubMed
Conversion of cholesterol to biologically active steroids is a multi-step enzymatic process. Along with some important enzymes, like cholesterol side-chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase/isomerase (3β-HSD), several proteins play key role in steroidogenesis. The role of steroidogenic acute regulatory (StAR) protein is well established. A novel protein, BRE, found mainly in brain, adrenals and gonads, was highly expressed in hyperplastic rat adrenals with impaired steroidogenesis, suggesting its regulation by pituitary hormones. To further elucidate its role in steroidogenic tissues, mouse Leydig tumor cells (mLTC-1) were transfected with BRE antisense probes. Morphologically the BRE antisense cells exhibited large cytoplasmic lipid droplets and failed to shrink in response to human chorionic gonadotropin. Although cAMP production, along with StAR and P450scc mRNA expression, was unaffected in BRE antisense clones, progesterone and testosterone yields were significantly decreased, while pregnenolone was increased in response to human chorionic gonadotropin stimulation or in the presence of 22(R)OH-cholesterol. Furthermore, whereas exogenous progesterone was readily converted to testosterone, pregnenolone was not, suggesting impairment of pregnenolone-to-progesterone conversion, a step metabolized by 3β-HSD. That steroidogenesis was compromised at the 3β-HSD step was further confirmed by the reduced expression of 3β-HSD type I (3ß-HSDI) mRNA in BRE antisense cells compared with controls. Our results suggest that BRE influences steroidogenesis through its effects on 3β-HSD action, probably affecting its transcription.
