Temperature-dependent Index of Mitotic Interval (τ0) for Chromosome Manipulation in Korean Bullhead, Pseudobagrus fulvidraco

Abstract

Korean bullhead (Pseudobagrus fulvidraco) was collected from the Kum River areas of Kangkyung-eup, Nonsan city, Chungcheongnam-do, Korea, from April to June, 2012 and was fertilized in order to observe egg development and temperature-related cleavage rates and mitotic intervals (τ0). The fertilized eggs were separative, demersal and light yellowish with 1.5±0.06 mm in diameter, and did not contain oil globules. The first cleavage stages were 90 min, 80 min, 60 min and 50 min at 21°C , 24°C , 27°C and 30°C , respectively. At higher temperatures, eggs developed faster and underwent further identical development. For Korean bullhead, τ0 were 33.4±2.08 min at 21°C, 31.5±3.06 min at 24°C, 28.1±2.11 min at 27°C and 26.4±3.35 min at 30°C . There were strong negative correlations between the τ0 and water temperatures at all points studied (Y= 1.13X+58.15, R2=0.98, n=30, where Y is τ0 and X is temperature). The results obtained in this work will be helpful for chromosome manipulation by use of cleavage frequency data and τ0 data in Korean bullhead.

Temperature Dependent of Mitotic Interval for Grass Puffer, Takifugu niphobles

“…Approximately 10% of fertilized eggs reached first cleavage frequency every 15 min. These results are similar to those reported by Ignat’eva (1975) , Saat & Veersalu (1996) , Park & Im (2001) , and Kim et al (2011) showing that faster development has occurred at higher water temperature.…”

“…3 , we found that grass puffer showed faster development with decreased mitotic intervals when water temperature was increased, indicating a strong negative correlation between τ 0 and water temperature. Besides this study, similar results on the reduction of mitotic interval according to rising water temperature have been reported in far eastern catfish ( Silurus asotus ) , black plaice ( Pleuronectes obscurus ), and Korean rose bitterling, Rhodeus uyekii ( Park & Im, 2001 ; Park and Im, 2010 ; Kim et al, 2011 ).…”

“…Of the four water temperature groups, τ 0 was 53±1.9 mins at 18℃, 49±2.3 mins at 20℃, 45±1.7 mins at 22℃, and 40±1.8 mins at 24℃. The duration of one mitotic cycle during the period of identical cell divisions (τ 0 ) has proven to be an appropriate unit for comparing the duration of development processes at different temperatures in poikilothermic animals undergoing identical cell divisions during their early development ( Shelton, 1993 , 1997 ; Park & Im, 2001 ; Kim et al, 2011 ). According to results shown in Fig.…”