Publications by authors named "Ekaterina R Kim"

3 Publications

  • Page 1 of 1

Transportin-1-dependent YB-1 nuclear import.

Biochem Biophys Res Commun 2016 Nov 26;480(4):629-634. Epub 2016 Oct 26.

Institute of Protein Research, Russian Academy of Sciences, 4 Institutskaya St., 142290, Pushchino, Moscow Region, Russia. Electronic address:

The DNA/RNA-binding protein YB-1 (Y-box binding protein 1) performs multiple functions both in the cytoplasm and the nucleus of the cell. Generally localized to the cytoplasm, under certain conditions YB-1 is translocated to the nucleus. Here we report for the first time a transport factor that mediates YB-1 nuclear import - transportin-1. The YB-1/transportin-1 complex can be isolated from HeLa cell extract. Nuclear import of YB-1 and its truncated form YB-1 (1-219) in in vitro transport assay was diminished in the presence of a competitor substrate and ceased in the presence of transportin-1 inhibitor M9M. Inhibitors of importin β1 had no effect on YB-1 transport. Furthermore, transport of YB-1 (P201A/Y202A) and YB-1 (1-219) (P201A/Y202A) bearing inactivating mutations in the transportin-1-dependent nuclear localization signal was practically abolished. Together, these results indicate that transportin-1 mediates YB-1 nuclear translocation.
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http://dx.doi.org/10.1016/j.bbrc.2016.10.107DOI Listing
November 2016

The proteolytic YB-1 fragment interacts with DNA repair machinery and enhances survival during DNA damaging stress.

Cell Cycle 2013 Dec 7;12(24):3791-803. Epub 2013 Oct 7.

Institute of Protein Research; Russian Academy of Sciences; Pushchino, Moscow Region, Russian Federation.

The Y-box binding protein 1 (YB-1) is a DNA/RNA-binding nucleocytoplasmic shuttling protein whose regulatory effect on many DNA and RNA-dependent events is determined by its localization in the cell. We have shown previously that YB-1 is cleaved by 20S proteasome between E219 and G220, and the truncated N-terminal YB-1 fragment accumulates in the nuclei of cells treated with DNA damaging drugs. We proposed that appearance of truncated YB-1 in the nucleus may predict multiple drug resistance. Here, we compared functional activities of the full-length and truncated YB-1 proteins and showed that the truncated form was more efficient in protecting cells against doxorubicin treatment. Both forms of YB-1 induced changes in expression of various genes without affecting those responsible for drug resistance. Interestingly, although YB-1 cleavage did not significantly affect its DNA binding properties, truncated YB-1 was detected in complexes with Mre11 and Rad50 under genotoxic stress conditions. We conclude that both full-length and truncated YB-1 are capable of protecting cells against DNA damaging agents, and the truncated form may have an additional function in DNA repair.
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http://dx.doi.org/10.4161/cc.26670DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3905071PMC
December 2013

Effect of the multifunctional proteins RPA, YB-1, and XPC repair factor on AP site cleavage by DNA glycosylase NEIL1.

J Mol Recognit 2012 Apr;25(4):224-33

Institute of Chemical Biology and Fundamental Medicine, Siberian Division of Russian Academy of Sciences, Prospect Lavrentieva 8, Novosibirsk, 630090, Russia.

DNA glycosylases are key enzymes in the first step of base excision DNA repair, recognizing DNA damage and catalyzing the release of damaged nucleobases. Bifunctional DNA glycosylases also possess associated apurinic/apyrimidinic (AP) lyase activity that nick the damaged DNA strand at an abasic (or AP) site, formed either spontaneously or at the first step of repair. NEIL1 is a bifunctional DNA glycosylase capable of processing lesions, including AP sites, not only in double-stranded but also in single-stranded DNA. Here, we show that proteins participating in DNA damage response, YB-1 and RPA, affect AP site cleavage by NEIL1. Stimulation of the AP lyase activity of NEIL1 was observed when an AP site was located in a 60 nt-long double-stranded DNA. Both RPA and YB-1 inhibited AP site cleavage by NEIL1 when the AP site was located in single-stranded DNA. Taking into account a direct interaction of YB-1 with the AP site, located in single-stranded DNA, and the high affinity of both YB-1 and RPA for single-stranded DNA, this behavior is presumably a consequence of a competition with NEIL1 for the DNA substrate. Xeroderma pigmentosum complementation group C protein (XPC), a key protein of another DNA repair pathway, was shown to interact directly with AP sites but had no effect on AP site cleavage by NEIL1.
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http://dx.doi.org/10.1002/jmr.2182DOI Listing
April 2012