Proliferating cell nuclear antigen in gonad and associated storage tissue of the Pacific oyster Crassostrea gigas: seasonal immunodetection and expression in laser microdissected tissues.
To understand the processes involved in tissue remodeling associated with the seasonal reproductive cycle of the oyster Crassostrea gigas, we used immunodetection and expression measurements of proliferating cell nuclear antigen (PCNA). The expression of the PCNA gene was measured by real-time polymerase chain reaction in the whole gonadal area compared with laser microdissected gonad and storage tissue. Results underlined the advantage of the laser microdissection approach to detect expression, mainly for early stages of spermatogenesis. In the storage tissue, PCNA expression was reduced in the gonadal tubules, but immunolabeled hemocytes and vesicular cells were detected when the storage tissue was being restored. In the gonadal tubules, the PCNA gene was more highly expressed in males than in females. As soon as spermatogenesis was initiated, PCNA expression showed a high and constant level. In females, the expression level increased gradually until the ripe stage. The immunological approach established the involvement of peritubular cells in gonadal tubule expansion during early gametogenesis. In both sexes, gonial mitosis was immunodetected throughout the reproductive cycle. In males, the occurrence of two types of spermatogonia was ascertained by differential immunolabeling, and intragonadal somatic cell proliferation was noted. As expected, immunolabeling was never observed from stage II spermatocytes to spermatozoa. In females, positively stained cells were detected from oogonia to growing oocytes with various labeled intracellular locations.
UMR 100 Ifremer, Physiologie et Ecophysiologie des Mollusques Marins, IFR 146 ICORE, Université de Caen Basse-Normandie, 14 032, Caen Cedex, France.
Alban
A
Franco
Aude
A
Jouaux
Michel
M
Mathieu
Pascal
P
Sourdaine
Christophe
C
Lelong
Kristell
K
Kellner
Clothilde
C
Heude Berthelin
D000818:Animals; D049109:Cell Proliferation; D049896:Crassostrea / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005854:Germ Cells / Q000166:cytology / Q000378:metabolism; D006066:Gonads / Q000166:cytology / Q000378:metabolism*; D006434:Hemocytes / Q000166:cytology / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D042282:Microdissection / Q000295:instrumentation / Q000379:methods; D018613:Microscopy, Confocal / Q000295:instrumentation / Q000379:methods; D008938:Mitosis / Q000502:physiology; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D009866:Oogenesis / Q000502:physiology; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism*; D012038:Regeneration / Q000502:physiology; D012098:Reproduction / Q000502:physiology*; D012621:Seasons; D012727:Sex Characteristics; D013045:Species Specificity; D013090:Spermatocytes / Q000166:cytology / Q000378:metabolism; D013091:Spermatogenesis / Q000502:physiology; D013093:Spermatogonia / Q000166:cytology / Q000378:metabolism
D018809:Proliferating Cell Nuclear Antigen