AN ANALYSIS OF THE INACTIVATION OF THE FROG SPERM NUCLEUS BY TOLUIDINE BLUE

Author:

Briggs Robert1

Affiliation:

1. From The Institute for Cancer Research and the Lankenau Hospital Research Institute, Philadelphia

Abstract

Toluidine blue, applied to frog sperm under appropriate conditions, inactivates specifically the sperm nucleus, leaving the extranuclear parts of the cell undamaged. Thus, the dye-treated spermatozoa stimulate eggs to cleave normally, but contribute no chromosomes to the resulting embryos, which develop as typical gynogenetic haploids. The concentration of dye required to produce this inactivation varies with pH. Measurements made over the entire pH range which can be tolerated by sperm cells showed that in the lower part of the range (5 to 7) the effective dye concentration was about 5 x 10–6 M; in the intermediate range (7 to 8.5) it was 1 x –6 to 1 x –7 M; and for the higher pH values (8.5 to 10.0) it was about 5 x –8 M. Using sperm suspensions containing 1500 cells per c. mm. these concentrations of dye produced specific inactivation of the sperm nuclei within 7 to 60 minutes at 18°C. Tests of the reversibility of the inactivation were made by transferring the sperm from the dye to a dilute Ringer's solution after a known degree of inactivation had been produced. Following removal of the dye the sperm cells were tested on eggs over a period of 2 hours. During this time there was no indication of a reversal of the inactivation. Microscopic observations of sperm treated with –5 M or 5 X –5 M dye show that the dye is taken up by the sperm nucleus, which is faintly but definitely stained. The dye appears to be uniformly distributed in the nucleus, while extranuclear structures remain unstained. Measurements of the amount of dye bound per sperm nucleus indicate that the minimal quantity required for complete inactivation is about 6.7 x –18 mole, while the maximal amount which can be bound without injury to extranuclear structures is about 1.5 x –16 mole. The value obtained for the minimal requirement (6.7 X 16 mole = 4 X 6 molecules) suggests that there are roughly 4 million binding sites in the nucleus which, when blocked by dye molecules, somehow prevent the sperm chromosomes from participating in the development of the egg.

Publisher

Rockefeller University Press

Subject

Physiology

Cited by 42 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3