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Abba promotes PDGF-mediated membrane ruffling through activation of the small GTPase Rac1

Datong Zheng1, Shuqiong Niu, Dan Yu

  • 1Second Hospital, The Second Clinical School, Nanjing Medical University, Jiangjiayuan 121, Nanjing, Jiangsu 210011, China.

Biochemical and Biophysical Research Communications
|September 30, 2010
PubMed

Insights

Abba protein interacts with Rac1 to regulate cell membrane shape changes, a process influenced by growth factors. This interaction is crucial for membrane ruffling and lamellipodia formation in cells.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Abba is an I-BAR domain protein involved in membrane dynamics.
  • Growth factor signaling pathways regulate cellular morphology.

Purpose of the Study:

  • To investigate the role of Abba protein in PDGF-mediated membrane ruffling and lamellipodia formation.
  • To elucidate the interaction between Abba and Rac1 GTPase.

Main Methods:

  • Overexpression of GFP-tagged Abba in murine fibroblasts.
  • Immunofluorescent microscopy and pull-down assays.
  • Immunoprecipitation assays and Rac GTPase activity assays.

Main Results:

  • Abba overexpression enhanced PDGF-induced membrane ruffles and lamellipodia.
  • GFP-Abba colocalized with active Rac1 and increased Rac GTPase activity.
  • Abba's Rac1-binding domain is essential for PDGF-mediated membrane remodeling.

Conclusions:

  • The interaction between Abba and Rac1 is critical for growth factor-regulated membrane deformation.
  • Abba's C-terminal sequence mediates growth factor-dependent regulation of Rac1 binding and cellular morphology.

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