An investigation of yolk-protein localization in the testes of the starfish Pisaster ochraceus

作者：Reunov Arkadiy A^*; Crawford Bruce J; Reunova Yulia A

来源：Canadian Journal of Zoology, 2010, 88(9): 914-921.

DOI：10.1139/Z10-060

The distribution of the yolk epitope, PY4F8, was studied in the testes of the starfish Pisaster ochraceus (Brandt, 1835). Western blots have revealed that testes only show one 180 kDa band, whereas ovaries exhibit four PY4F8 bands at 90, 110, 120, and 180 kDa. This finding suggests that male yolk is less complex than female yolk. It was shown that PY4F8-positive material abounds in the hemal sinus of testes. Moreover, this epitope was found in the basal lamina, in the lumen of the testes, and in the cytoplasm of auxiliary and spermatogenic cells. It is likely that a hemal testis barrier is absent in P. ochraceus, and this lack allows direct penetration of nutrition to sustain metabolism of both spermatogenic and auxiliary cells. Morphologically, this penetration is possible through the gaps between adjacent auxiliary cell bases. Yolk granules containing the PY4F8 epitope are located in spermatogonia and spermatocytes, but not in spermatids and sperm. Therefore, yolk may play an important role in early spermatogenesis, but it does not participate at the final stage of sperm formation.

• 出版日期2010-9