Chapter 13 Visualization of Dynamins

Mears, Jason A.; Hinshaw, Jenny E.

doi:10.1016/s0091-679x(08)00413-5

Cited by 24 publications

(20 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Classical dynamins are known to undergo stimulated GTPase activity upon lipid-induced self-assembly [37], [63], an event that has also been described for some dynamin-like proteins [40], [41]. Thus, we decided to investigate structural changes occurring in Drp1 upon interaction with CL.…”

Section: Resultsmentioning

confidence: 94%

Specific Interaction with Cardiolipin Triggers Functional Activation of Dynamin-Related Protein 1

et al. 2014

View full text Add to dashboard Cite

Dynamin-Related Protein 1 (Drp1), a large GTPase of the dynamin superfamily, is required for mitochondrial fission in healthy and apoptotic cells. Drp1 activation is a complex process that involves translocation from the cytosol to the mitochondrial outer membrane (MOM) and assembly into rings/spirals at the MOM, leading to membrane constriction/division. Similar to dynamins, Drp1 contains GTPase (G), bundle signaling element (BSE) and stalk domains. However, instead of the lipid–interacting Pleckstrin Homology (PH) domain present in the dynamins, Drp1 contains the so-called B insert or variable domain that has been suggested to play an important role in Drp1 regulation. Different proteins have been implicated in Drp1 recruitment to the MOM, although how MOM-localized Drp1 acquires its fully functional status remains poorly understood. We found that Drp1 can interact with pure lipid bilayers enriched in the mitochondrion-specific phospholipid cardiolipin (CL). Building on our previous study, we now explore the specificity and functional consequences of this interaction. We show that a four lysine module located within the B insert of Drp1 interacts preferentially with CL over other anionic lipids. This interaction dramatically enhances Drp1 oligomerization and assembly-stimulated GTP hydrolysis. Our results add significantly to a growing body of evidence indicating that CL is an important regulator of many essential mitochondrial functions.

show abstract

Section: Resultsmentioning

confidence: 94%

Specific Interaction with Cardiolipin Triggers Functional Activation of Dynamin-Related Protein 1

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Similar to yeast DNM1, human DRP1 assembles into higher order oligomers, forming curved filaments and occasional rings in the presence of low salt conditions or rings and spiral-like structures in the presence of non-hydrolyzable nucleotides [23, 39]. To test whether S-nitrosylation of DRP1 increases its ability to self-assemble, which would be consistent with increased activation, we used negative stain and transmission electron microscopy to visualize oligomerization.…”

Section: Resultsmentioning

confidence: 99%

S-Nitrosylation of DRP1 Does Not Affect Enzymatic Activity and is Not Specific to Alzheimer's Disease

Bossy

Petrilli

Klinglmayr

et al. 2010

JAD

148

125

View full text Add to dashboard Cite

Abstract. Mitochondrial dysfunction and synaptic loss are among the earliest events linked to Alzheimer's disease (AD) and might play a causative role in disease onset and progression. The underlying mechanisms of mitochondrial and synaptic dysfunction in AD remain unclear. We previously reported that nitric oxide (NO) triggers persistent mitochondrial fission and causes neuronal cell death. A recent article claimed that S-nitrosylation of dynamin related protein 1 (DRP1) at cysteine 644 causes protein dimerization and increased GTPase activity and is the mechanism responsible for NO-induced mitochondrial fission and neuronal injury in AD, but not in Parkinson's disease (PD). However, this report remains controversial. To resolve the controversy, we investigated the effects of S-nitrosylation on DRP1 structure and function. Contrary to the previous report, S-nitrosylation of DRP1 does not increase GTPase activity or cause dimerization. In fact, DRP1 does not exist as a dimer under native conditions, but rather as a tetramer capable of self-assembly into higher order spiral-and ring-like oligomeric structures after nucleotide binding. S-nitrosylation, as confirmed by the biotin-switch assay, has no impact on DRP1 oligomerization. Importantly, we found no significant difference in S-nitrosylated DRP1 (SNO-DRP1) levels in brains of age-matched normal, AD, or PD patients. We also found that S-nitrosylation is not specific to DRP1 because S-nitrosylated optic atrophy 1 (SNO-OPA1) is present at comparable levels in all human brain samples. Finally, we show that NO triggers DRP1 phosphorylation at serine 616, which results in its activation and recruitment to mitochondria. Our data indicate the mechanism underlying nitrosative stress-induced mitochondrial fragmentation in AD is not DRP1 S-nitrosylation.

show abstract

“…Sedimentation Assay-To quantify Drp1 oligomerization, a sedimentation assay was conducted similar to what has been described previously (34,35). Large oligomers formed by Drp1 samples, in the presence of ligands, were found in the pellet after a medium speed centrifugation.…”

Section: Methodsmentioning

confidence: 99%

The Mechanoenzymatic Core of Dynamin-related Protein 1 Comprises the Minimal Machinery Required for Membrane Constriction

Francy¹,

Alvarez²,

Zhou³

et al. 2015

Journal of Biological Chemistry

Self Cite

137

View full text Add to dashboard Cite

Background: Drp1 oligomerization and activity is critical for mitochondrial fission. Results: GTP hydrolysis is required for Drp1 constriction of lipid bilayers. The variable domain of Drp1 regulates self-assembly and is not required for constriction of lipid bilayers. Conclusion:The core machinery of Drp1 is sufficient to mediate lipid assembly, constriction, and disassembly. Significance: Characterization of the mechanoenzymatic properties of Drp1 advances our understanding of mitochondrial fission.

show abstract

Chapter 13 Visualization of Dynamins

Cited by 24 publications

References 53 publications

Specific Interaction with Cardiolipin Triggers Functional Activation of Dynamin-Related Protein 1

Specific Interaction with Cardiolipin Triggers Functional Activation of Dynamin-Related Protein 1

S-Nitrosylation of DRP1 Does Not Affect Enzymatic Activity and is Not Specific to Alzheimer's Disease

The Mechanoenzymatic Core of Dynamin-related Protein 1 Comprises the Minimal Machinery Required for Membrane Constriction

Contact Info

Product

Resources

About