Authors : Liu Yong, Ding Biao, Wu Fengrui, Wang Rong, Yang Xuxun, Shang Mingbao and Li Wenyong
Abstract: There is a lack of quantitive and objective method study the chromatin configuration of mammalian oocytes. This study attempts to solve this problem. The Germinal Vesicle (GV) chromatin was stained with Hoechst33342 and photos were taken under the fluorescence microscope. The photos are then processed and the Integral Optical Density (IOD) of fluorescent areas and areas of germinal vesicle are measured. The researchers regard the IODs of fluorescent areas as Aggregation Degree (AD) and the ratio of fluorescent areas to the areas of GV as Spatial Distribution (SD). According to the traditional classification method of chromatin configuration in mouse, pig and goat, the researchers divided the photos of chromatin into several groups and calculated the AD, SD and IOD of chromatin configuration in these three species. The conclusions are as follows: quantitative fluorescence analysis technology established in this study can be applied in studying the chromatin configuration of mammalian oocytes. All the oocytes with poor capability to resume meiosis and support embryo development have a common feature that the value of AD is the smallest and the value of SD is the biggest in their own species. SD is a key parameter of chromatin configuration in relation to transcription. Transcription continued when SD>0.4 and ceased when SD<0.3. The value of AD increased and the value of SD decreased when the capabilities of the oocytes to resume meiosis and to support embryo development were enhanced. The value of IOD does not vary in healthy oocytes during the follicular growth stage.
Liu Yong, Ding Biao, Wu Fengrui, Wang Rong, Yang Xuxun, Shang Mingbao and Li Wenyong, 2012. A Novel Oocyte Chromatin Configuration Classification Method: Based on the Degree of Aggregation and Spatial Distribution of Germinal Vesicle Chromatin. Journal of Animal and Veterinary Advances, 11: 531-538.