ABSTRACT
Effects of water temperature and hormones on ovarian development of conger eel in Korea were investigated. Ovarian development was analyzed by measuring gonadosomatic index (GSI) and oocyte diameter with histological methods. At rearing water temperatures of 12°C, 14°C, and 16°C, GSI value increased from 3.66 at the start of the experiment to 7.44, 8.82, and 7.34 at the end of the experiment, respectively. At rearing water temperatures of 12°C, 14°C, and 16°C, egg diameter increased from 245.11-300.25 µm at the start of the experiment to 377.62-480.27 µm, 396.72-498.54 µm, and 382.29-475.69 µm at the end of the experiment, respectively. Follicular oocyte development revealed that primary yolk globule stage observed from January to March. It entered to secondary yolk globule stage in April and remained at the same stage until July. As a result of examining effects of three hormones (human chorionic gonadotropin (HCG), luteinizing hormone releasing hormone analogue (LHRHa), and salmon pituitary extraction (SPE) on ovarian development, HCG was found to be the most effective one. The progress from diapause of the secondary yolk globule stage to migratory nucleus stage of oocytes could be induced by treating fish with HCG at 1,000 IU/kg. The effect of hormone treatment on ovarian development of conger eel in Korea was the most effective at water temperature of 14°C.
ABSTRACT
SPIN90, a 90-kDa Nck-interacting protein with a SH3 domain, plays a role in sarcomere formation and myofibril assembly, and its phosphorylation is modulated by cell adhesion and Erk activation. Here we demonstrate that SPIN90 participates in receptor-mediated endocytic pathway in fibroblasts. We identified syndapin (synaptic dynamin-binding protein) as a SPIN90 interacting protein using yeast two-hybrid screening. SPIN90 directly binds the SH3 domain of syndapin via its proline rich domain in vitro and in vivo and also associates with clathrin. Over-expression of SPIN90-full length in COS-7 cells inhibited transferrin uptake, a marker of endocytosis. Interestingly, SPIN90-PRD, a syndapin-binding domain, significantly inhibited endocytosis, and the inhibition was reversed by co-expression of syndapin. Depleting SPIN90 through antibody microinjection or Knocking it down using siRNAs also significantly inhibited transferrin internalization. Moreover, early endosomal marker proteins (EEA1 and Rab5) appeared to closely associate or partially co-localize with SPIN90 in endosomes and an internalized FITC-dextran and Texas Red-EGF were found on the endosomes in association with SPIN90. Time-lapse video showed that GFP-SPIN90 travels with moving vesicles within living cells. Taken together, these findings suggest that SPIN90 is implicated in receptor-mediated endocytic pathway in fibroblasts.