Ryan Baldridge, Ph.D.

Assistant Professor, Biological Chemistry

Ofc:  3220E MSRB III

Lab:  3200   MSRB III

1150 W. Medical Center Drive

Ann Arbor, MI  48109-5606


Ofc Ph:   (734) 763-4008

Lab Ph:   (734) 936-3440


(734) 763-4008

Areas of Interest

Membrane biology, protein quality control, ubiquitination 

We are interested in the basic mechanisms of membrane-bound protein-quality control systems. We plan to determine how membrane-bound systems select substrates to identify cellular pathways regulated by these systems (including ERAD). These systems are important in pathologies related to cell stress, protein misfolding, and protein misregulation. Some of the human conditions linked to these problems include Parkinson’s disease, Alzheimer’s disease, and various cancers. One of our long-term goals is to define mammalian pathways regulated by membrane-bound quality control systems to understand how changing conditions target substrate proteins to these systems. Eventually, we would like to develop a screening platform to identify activators and inhibitors of these various quality control systems. Understanding these systems using novel assays should allow screening for, and refinement of, therapeutics with value in a wide range of pathologies.


Lab members:

Sagar Lahiri, Ph.D.
Postdoctoral Fellow
Morgan Freigang, M.A.
Senior Research Technician

Published Articles or Reviews

Baldridge, R.D* and Rapoport, T.A.* (2016) Autoubiquitination of the Hrd1 ligase triggers protein retrotranslocation in ERAD. Cell. 166: 394-407.
(*co-corresponding authors).  (Highlighted:  Strzyz, P. (2016) Nat Rev Mol Cell Biol;   Zhang, T. and Ye, Y. (2016) Cell Res)

Hankins, H.M., Baldridge, R.D., Xu, P. and Graham, T.R. (2015) Role of flippases, scramblases, and transfer proteins in phosphatidylserine subcellular distribution. Traffic. 16: 35-47. (Review)

Xu, P., Baldridge, R.D., Chi, R. Burd, C.G. and Graham, T.R. (2013) Phosphatidylserine translocation by a P4-ATPase induces curvature and charge required for vesicular transport. J Cell Biol. 202: 875-86.  (Highlighted: Leslie, M. (2013) J Cell Biol)

Baldridge, R.D., Xu, P. and Graham, T.R. (2013) Type IV P-type ATPases distinguish mono- versus di-acyl phosphatidylserine using a cytofacial exit gate in the membrane domain. J Biol Chem. 288: 19516-27.

Baldridge, R.D. and Graham, T.R. (2013) Two-gate mechanism for phospholipid selection and transport by type IV P-type ATPases. Proc Natl Acad Sci USA. 110: E358-67.

Baldridge, R.D. and Graham, T.R. (2012) Identification of residues defining phospholipid flippase substrate specificity of type IV P-type ATPases. Proc Natl Acad Sci USA. 109: E290-8.

Sebastian, T.T.*, Baldridge, R.D.*, Xu, P. and Graham, T.R. (2012) Phospholipid flippases: building asymmetric membranes and transport vesicles. Biochim Biophys Acta. 1821: 1068-77. (Review)

(*co-first authors)

For a complete list of this person’s PubMed publications, click HERE

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