Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23
Proteins destined for the mitochondrial matrix are targeted to the inner membrane Tim17/23 translocon by their presequences. Inward movement is driven by the matrix-localized, Hsp70-based motor. The scaffold Tim44, interacting with the matrix face of the translocon, recruits other motor subunits and...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
eLife Sciences Publications Ltd
2017-04-01
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| Series: | eLife |
| Subjects: | |
| Online Access: | https://elifesciences.org/articles/23609 |
| _version_ | 1811252855602937856 |
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| author | See-Yeun Ting Nicholas L Yan Brenda A Schilke Elizabeth A Craig |
| author_facet | See-Yeun Ting Nicholas L Yan Brenda A Schilke Elizabeth A Craig |
| author_sort | See-Yeun Ting |
| collection | DOAJ |
| description | Proteins destined for the mitochondrial matrix are targeted to the inner membrane Tim17/23 translocon by their presequences. Inward movement is driven by the matrix-localized, Hsp70-based motor. The scaffold Tim44, interacting with the matrix face of the translocon, recruits other motor subunits and binds incoming presequence. The basis of these interactions and their functional relationships remains unclear. Using site-specific in vivo crosslinking and genetic approaches in Saccharomyces cerevisiae, we found that both domains of Tim44 interact with the major matrix-exposed loop of Tim23, with the C-terminal domain (CTD) binding Tim17 as well. Results of in vitro experiments showed that the N-terminal domain (NTD) is intrinsically disordered and binds presequence near a region important for interaction with Hsp70 and Tim23. Our data suggest a model in which the CTD serves primarily to anchor Tim44 to the translocon, whereas the NTD is a dynamic arm, interacting with multiple components to drive efficient translocation. |
| first_indexed | 2024-04-12T16:41:55Z |
| format | Article |
| id | doaj.art-0104b2f18b76410d93481b1db0836fac |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-12T16:41:55Z |
| publishDate | 2017-04-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-0104b2f18b76410d93481b1db0836fac2022-12-22T03:24:45ZengeLife Sciences Publications LtdeLife2050-084X2017-04-01610.7554/eLife.23609Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23See-Yeun Ting0Nicholas L Yan1Brenda A Schilke2Elizabeth A Craig3https://orcid.org/0000-0002-9381-4307Department of Biochemistry, University of Wisconsin-Madison, Madison, United StatesDepartment of Biochemistry, University of Wisconsin-Madison, Madison, United StatesDepartment of Biochemistry, University of Wisconsin-Madison, Madison, United StatesDepartment of Biochemistry, University of Wisconsin-Madison, Madison, United StatesProteins destined for the mitochondrial matrix are targeted to the inner membrane Tim17/23 translocon by their presequences. Inward movement is driven by the matrix-localized, Hsp70-based motor. The scaffold Tim44, interacting with the matrix face of the translocon, recruits other motor subunits and binds incoming presequence. The basis of these interactions and their functional relationships remains unclear. Using site-specific in vivo crosslinking and genetic approaches in Saccharomyces cerevisiae, we found that both domains of Tim44 interact with the major matrix-exposed loop of Tim23, with the C-terminal domain (CTD) binding Tim17 as well. Results of in vitro experiments showed that the N-terminal domain (NTD) is intrinsically disordered and binds presequence near a region important for interaction with Hsp70 and Tim23. Our data suggest a model in which the CTD serves primarily to anchor Tim44 to the translocon, whereas the NTD is a dynamic arm, interacting with multiple components to drive efficient translocation.https://elifesciences.org/articles/23609protein translocationHsp70mitochondria |
| spellingShingle | See-Yeun Ting Nicholas L Yan Brenda A Schilke Elizabeth A Craig Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23 eLife protein translocation Hsp70 mitochondria |
| title | Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23 |
| title_full | Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23 |
| title_fullStr | Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23 |
| title_full_unstemmed | Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23 |
| title_short | Dual interaction of scaffold protein Tim44 of mitochondrial import motor with channel-forming translocase subunit Tim23 |
| title_sort | dual interaction of scaffold protein tim44 of mitochondrial import motor with channel forming translocase subunit tim23 |
| topic | protein translocation Hsp70 mitochondria |
| url | https://elifesciences.org/articles/23609 |
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