ISSN:
1432-0878
Keywords:
Calcineurin
;
Spermatogenesis
;
Spermatids
;
Nuclear transformation
;
Immunohistochemistry
;
Mouse (Jcl:ICR, BALB/c)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract Immunohistochemical localization of a calmodulin-dependent protein phosphatase, calcineurin, was studied in the mouse testis in relation to previous observations showing that calmodulin is unusually rich in spermatogenic stages from mid-pachytene spermatocytes to elongating spermatids. The antibodies raised against calcineurin from scallop testis reacted with subunit B, but not subunit A, of calcineurin isoforms from mouse brain and testis. Indirect immunofluorescence using these antibodies on the mouse testis revealed positive reactions only in the nuclei of round or elongating spermatids: calcineurin started to accumulate in nuclei from the acrosomal cap phase, peaked at the initial stage of nuclear elongation, and decreased thereafter. There was almost no signal in the cytoplasm; spermatogenic cells at other stages, including spermatogonia, spermatocytes, mature sperm, and other somatic cells in the seminiferous tubules were totally negative. Immuno-electron microscopy gave the same result, on the basis of measuring the density of immunogold particles. These results suggest a role for calcineurin in remodeling of the nuclear chromatin in metamorphosing spermatids.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00583396
