Glom Is a Novel Mitochondrial DNA Packaging Protein inPhysarum polycephalumand Causes Intense Chromatin Condensation without Suppressing DNA Functions

Author:

Sasaki Narie1,Kuroiwa Haruko2,Nishitani Chikako3,Takano Hiroyoshi4,Higashiyama Tetsuya3,Kobayashi Tamaki3,Shirai Yuki1,Sakai Atsushi5,Kawano Shigeyuki6,Murakami-Murofushi Kimiko1,Kuroiwa Tsuneyoshi2

Affiliation:

1. Department of Biology, Faculty of Science, Ochanomizu University, Tokyo, Japan

2. Department of Life Science, College of Science, Rikkyo (St. Paul's) University, Tokyo, Japan

3. Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan

4. Department of Biological Science, Faculty of Science, Kumamoto University, Kumamoto, Japan

5. Department of Biology, Faculty of Science, Nara Women's University, Nara, Japan

6. Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Chiba, Japan

Abstract

Mitochondrial DNA (mtDNA) is packed into highly organized structures called mitochondrial nucleoids (mt-nucleoids). To understand the organization of mtDNA and the overall regulation of its genetic activity within the mt-nucleoids, we identified and characterized a novel mtDNA packaging protein, termed Glom (a protein inducing agglomeration of mitochondrial chromosome), from highly condensed mt-nucleoids of the true slime mold, Physarum polycephalum. This protein could bind to the entire mtDNA and package mtDNA into a highly condensed state in vitro. Immunostaining analysis showed that Glom specifically localized throughout the mt-nucleoid. Deduced amino acid sequence revealed that Glom has a lysine-rich region with proline-rich domain in the N-terminal half and two HMG boxes in C-terminal half. Deletion analysis of Glom revealed that the lysine-rich region was sufficient for the intense mtDNA condensation in vitro. When the recombinant Glom proteins containing the lysine-rich region were expressed in Escherichia coli, the condensed nucleoid structures were observed in E. coli. Such in vivo condensation did not interfere with transcription or replication of E. coli chromosome and the proline-rich domain was essential to keep those genetic activities. The expression of Glom also complemented the E. coli mutant lacking the bacterial histone-like protein HU and the HMG-boxes region of Glom was important for the complementation. Our results suggest that Glom is a new mitochondrial histone-like protein having a property to cause intense DNA condensation without suppressing DNA functions.

Publisher

American Society for Cell Biology (ASCB)

Subject

Cell Biology,Molecular Biology

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