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Published on: October 17, 2014
Regulation of cell shape and adhesion by CD34
Hiroe Ohnishi1, Hiroyuki Sasaki2, Yoshihiko Nakamura3
1Research Center for Medical Glycoscience; National Institute of Advanced Industrial Science and Technology (AIST); Umezono, Tsukuba, Ibaraki, Japan; Health Research Institute; AIST; Nakouji, Amagasaki, Hyogo, Japan.
Cell Adhesion & Migration
|September 17, 2013
Summary
CD34, a cell surface protein, inhibits cell adhesion, promoting cell rounding and microvillus formation. This function is linked to ezrin/radixin/moesin (ERM) protein phosphorylation and impacts hematopoietic progenitor cell behavior.
Area of Science:
- Cell Biology
- Hematology
- Molecular Biology
Background:
- CD43/leukosialin was previously shown to inhibit cell adhesion, inducing cell rounding and microvillus formation.
- CD34 is a known cell surface sialomucin and a marker for hematopoietic progenitor cells.
Purpose of the Study:
- To investigate the role of CD34 in cell adhesion and cell morphology.
- To determine if CD34 affects integrin-mediated cell re-attachment and cell shape.
- To explore the involvement of ezrin/radixin/moesin (ERM) proteins in CD34-mediated effects.
Main Methods:
- Forced expression of CD34 in HEK293T cells.
- Analysis of cell rounding, microvillus formation, and ERM protein phosphorylation.
- Assessment of integrin-mediated cell re-attachment.
- Examination of CD34+ blood cells and KG-1 cells for cell shape and adhesion properties.
- Cleavage of O-sialomucin to observe effects on cell adhesion.
Main Results:
- Forced CD34 expression induced cell rounding, microvillus formation, and ERM protein phosphorylation in HEK293T cells.
- CD34 inhibited integrin-mediated cell re-attachment.
- Endogenous CD34 on blood cells and KG-1 cells correlated with spherical shape, microvilli, and non-adherence.
- O-sialomucin cleavage enhanced integrin-mediated adhesion in KG-1 cells.
Conclusions:
- CD34 actively inhibits integrin-mediated cell adhesion, influencing cell surface structure formation.
- Phosphorylation of ERM proteins is a likely mechanism through which CD34 modulates cell adhesion and shape.
- The spherical shape and microvilli observed in CD34+ cells may play a role in regulating cell adhesion dynamics.
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