Structural and functional study of Legionella pneumophila effector RavA
Ivy Y W Chung1, Lei Li1, Oleg Tyurin1,2
1Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Protein Science : a Publication of the Protein Society
|March 4, 2021
Summary
This study reveals Legionella pneumophila effector RavA
Area of Science:
- Microbiology
- Cell Biology
- Structural Biology
Background:
- Legionella pneumophila causes Legionnaires' disease by infecting human cells.
- The Dot/Icm type IV secretion system delivers over 300 effector proteins into host cells.
- The functions of many L. pneumophila Dot/Icm effectors remain uncharacterized.
Purpose of the Study:
- To investigate the structure and function of the L. pneumophila effector protein RavA (Lpg0008).
- To determine the cellular localization and host interactions of RavA during infection.
Main Methods:
- Structural analysis of RavA using biophysical techniques.
- Cellular localization studies in human cells during L. pneumophila infection.
- Yeast-two-hybrid screening to identify RavA binding partners.
Main Results:
- RavA possesses a unique structure with four α-helical domains and an intrinsically disordered C-terminus.
- RavA localizes to the Golgi apparatus and plasma membrane in infected human cells.
- The C-terminal sequence C409WTSFCGLF417 mediates RavA localization.
- RAB11A was identified as a potential binding partner of RavA.
Conclusions:
- RavA is a novel L. pneumophila effector with a unique structure and specific cellular localization.
- RavA's interaction with RAB11A suggests a role in host-pathogen interactions and intracellular trafficking.
- Further studies on RavA will elucidate its precise function in L. pneumophila pathogenesis.
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