[Expression of germ cell nuclear factor in rat epididymis during postnatal development].
OBJECTIVE
To explore the expression and distribution of germ cell nuclear factor (GCNF), an orphan receptor of the nuclear receptor superfamily which is supposed to have multifunction including spermatogenesis, neurogenesis and embryo development, in adult rat epididymis and young rats during postnatal development.


METHODS
Whole epididymis was collected from SD rats' aged 7, 14, 28, 45, 60 and 90 days, and 18 months. The protein expression of GCNF during rat epididymal development and its cellular localizations were examined by Western blotting and immunohistochemistry respectively.


RESULTS
GCNF was immunolocalized in the nuclei of epididymal epithelial cells with negatively stained cytoplasm in rats during postnatal development. Study of postnatal development revealed that the density of GCNF protein (about 55000) was age-dependent. GCNF protein was first detected in the rats aged day 14. The number and intensity of positive cells increased along with differentiation and proliferation of the epithelium, and peaked when the rats were aged 45 days and then decreased gradually. The results of Western-blotting confirmed those of immunohistochemistry. In adult rats, basal cell, apical cell, narrow cell, and clear cell and halo cell. GCNF in the principal cells exhibited a region-specific and cell-specific expression pattern that was observed from the age of 14 days. The GCNF expression was gradually decreased from the initial segment to proximal cauda epididymis. There was a predominant expression in the proximal caput region. The principal cells in the same segment also displayed a variable staining pattern, with the nucleus being intensely, moderately, or weekly reactive. In the distal cauda epididymis, only the nuclei of clear cells displayed an intensive staining, as compared with very weak staining in the principal cells.


CONCLUSIONS
The expression of GCNF may be concerned with the differentiation and development of epididymal epithelium, and its expression pattern is epididymal segment-specific and cell-specific.
Department of Histology & Embryology, Research Center of Reproductive Medicine, School of Medicine, Xi'an Jiaotang University, China.
Qiu-Yang
QY
Zhang
Shu-Dong
SD
Qiu
Jie
J
Yang
D000367:Age Factors; D000818:Animals; D004268:DNA-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D004822:Epididymis / Q000737:chemistry* / Q000166:cytology / Q000254:growth & development*; D007150:Immunohistochemistry; D008297:Male; D057136:Nuclear Receptor Subfamily 6, Group A, Member 1; D051381:Rats; D017207:Rats, Sprague-Dawley; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis* / Q000235:genetics
D004268:DNA-Binding Proteins; C539956:Nr6a1 protein, rat; D057136:Nuclear Receptor Subfamily 6, Group A, Member 1; D018160:Receptors, Cytoplasmic and Nuclear