Zhu G, Hsu K G, Wang Y W, Gu Z, Tso J K
Shanghai Institute of Cell Biology, Academia Sinica.
Shi Yan Sheng Wu Xue Bao. 1993 Dec;26(4):469-82.
Full-grown oocytes derived from Bufo bufo gargarizans rearing in high temperature environment (28-30 degrees C), called high temperature oocytes, never underwent germinal vesicle breakdown (GVBD) after progesterone stimulation, no MPF was detected in their ooplasm, but some events which manifested normally at the beginning of progesterone induced maturation process were revealed in these oocytes. It is worth notice an another kind of maturation promoting substance(s) appeared in the ooplasm of high temperature oocyte after the hormone treatment, which was capable of triggering the resumption of meiotic division of the full-grown oocytes derived from hibernating toad (called low temperature oocytes). It is a hibernation factor-dependent maturation promoting substance (HF-MPS), which appeared after decrease of the oocyte endogenous cAMP level. Its appearance depended upon the oocyte protein synthesis, and its activity to inducing GVBD of low temperature oocytes did not inhibited by puromycin. HF-MPS differs from MPF in maturation promoting activity, as low temperature (10 degrees C) delayed obviously HF-MPS' activity but did not influence the rate of GVBD induced by MPF. Further more, probably due to the lack of "hibernation factor(s)", no expression of p34cdc2 gene was detected in high temperature oocytes (unpublished data), neither HF-MPS nor MPF could amplify autocatalytically in the oocytes. So the low temperature (below 15 degrees C) was found to be indispensable for the toad oocyte maturation. If one day we can prove HF-MPS appeared also in the course of oocyte maturation induced by progesterone, the relationship between HF-MPS and MPF may be: [formula: see text] All these discoveries indicated above make a reasonable explanation of the geographical distribution of the toad which was restricted in the region north to the 23 degrees north latitude and east to the 100 degrees east longitude in China.
来源于中华大蟾蜍并在高温环境（28 - 30摄氏度）中饲养的成熟卵母细胞，称为高温卵母细胞，在孕酮刺激后从未发生生发泡破裂（GVBD），其卵质中未检测到MPF，但这些卵母细胞中出现了一些在孕酮诱导的成熟过程开始时正常表现的事件。值得注意的是，激素处理后高温卵母细胞的卵质中出现了另一种成熟促进物质，它能够触发来自冬眠蟾蜍的成熟卵母细胞（称为低温卵母细胞）减数分裂的恢复。这是一种依赖冬眠因子的成熟促进物质（HF - MPS），在卵母细胞内源性cAMP水平降低后出现。它的出现依赖于卵母细胞蛋白质合成，其诱导低温卵母细胞GVBD的活性不受嘌呤霉素抑制。HF - MPS在成熟促进活性方面与MPF不同，因为低温（10摄氏度）明显延迟了HF - MPS的活性，但不影响MPF诱导GVBD的速率。此外，可能由于缺乏“冬眠因子”，在高温卵母细胞中未检测到p34cdc2基因的表达（未发表数据），HF - MPS和MPF在卵母细胞中均不能自催化扩增。因此发现低温（低于15摄氏度）对于蟾蜍卵母细胞成熟是必不可少的。如果有一天我们能够证明HF - MPS也出现在孕酮诱导的卵母细胞成熟过程中，那么HF - MPS与MPF之间的关系可能是：[公式：见正文]上述所有这些发现对蟾蜍在中国北纬23度以北、东经100度以东地区的地理分布做出了合理的解释。
