Unknown

Dataset Information

0

Positively charged residues within the MYO19 MyMOMA domain are essential for proper localization of MYO19 to the mitochondrial outer membrane.


ABSTRACT: Myosins are well characterized molecular motors essential for intracellular transport. MYO19 copurifies with mitochondria, and can be released from mitochondrial membranes by high pH buffer, suggesting that positively-charged residues participate in interactions between MYO19 and mitochondria. The MYO19-specific mitochondria outer membrane association (MyMOMA) domain contains approximately 150 amino acids with a pI approximately 9 and is sufficient for localization to the mitochondrial outer membrane. The minimal sequence and specific residues involved in mitochondrial binding have not been identified. To address this, we generated GFP-MyMOMA truncations, establishing the boundaries for truncations based on sequence homology. We identified an 83-amino acid minimal binding region enriched with basic residues (pI ? 10.5). We sequentially replaced basic residues in this region with alanine, identifying residues R882 and K883 as essential for mitochondrial localization. Constructs containing the RK882-883AA mutation primarily localized with the endoplasmic reticulum (ER). To determine if ER-associated mutant MyMOMA domain and mitochondria-associated wild type MyMOMA display differences in kinetics of membrane interaction, we paired FRAP analysis with permeabilization activated reduction in fluorescence (PARF) analysis. Mitochondria-bound and ER-bound MYO19 constructs displayed slow dissociation from their target membrane when assayed by PARF; both constructs displayed exchange within their respective organelle networks. However, ER-bound mutant MYO19 displayed more rapid exchange within the ER network than did mitochondria-bound MYO19. Taken together these data indicate that the MyMOMA domain contains strong membrane-binding activity, and membrane targeting is mediated by a specific, basic region of the MYO19 tail with slow dissociation kinetics appropriate for its role(s) in mitochondrial network dynamics. © 2016 Wiley Periodicals, Inc.

SUBMITTER: Hawthorne JL 

PROVIDER: S-EPMC4909549 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

altmetric image

Publications

Positively charged residues within the MYO19 MyMOMA domain are essential for proper localization of MYO19 to the mitochondrial outer membrane.

Hawthorne Jenci L JL   Mehta Prachi R PR   Singh Pali P PP   Wong Nathan Q NQ   Quintero Omar A OA  

Cytoskeleton (Hoboken, N.J.) 20160524 6


Myosins are well characterized molecular motors essential for intracellular transport. MYO19 copurifies with mitochondria, and can be released from mitochondrial membranes by high pH buffer, suggesting that positively-charged residues participate in interactions between MYO19 and mitochondria. The MYO19-specific mitochondria outer membrane association (MyMOMA) domain contains approximately 150 amino acids with a pI approximately 9 and is sufficient for localization to the mitochondrial outer mem  ...[more]

Similar Datasets

| S-EPMC4702679 | biostudies-literature
| S-EPMC3595205 | biostudies-literature
| S-EPMC3916562 | biostudies-literature
| S-EPMC6161257 | biostudies-literature
| S-EPMC5129775 | biostudies-literature
| S-EPMC3836577 | biostudies-literature
| S-EPMC5213669 | biostudies-literature
| S-EPMC2393759 | biostudies-literature
| S-EPMC8720280 | biostudies-literature
| S-EPMC3025461 | biostudies-literature