Two stage cadherin kinetics require multiple extracellular domains but not the cytoplasmic region.
Micropipette manipulation measurements quantified the pre-steady state binding kinetics between cell pairs mediated by Xenopus cleavage stage cadherin. The time-dependence of the intercellular binding probability exhibits a fast forming, low probability binding state, which transitions to a slower forming, high probability state. The biphasic kinetics are independent of the cytoplasmic region, but the transition to the high probability state requires the third extracellular domain EC3. Deleting either EC3 or EC3-5, or substituting Trp(2) for Ala reduces the binding curves to a simple, monophasic rise in binding probability to a limiting plateau, as predicted for a single site binding mechanism. The two stage cadherin binding process reported here directly parallels previous biophysical studies, and confirms that the cadherin ectodomain governs the initial intercellular adhesion dynamics.
Chien
Yuan-Hung
YH
Department of Biochemistry, University of Illinois, Urbana, Illinois, USA.
Jiang
Ning
N
Li
Fang
F
Zhang
Fang
F
Zhu
Cheng
C
Leckband
Deborah
D
D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002448:Cell Adhesion / Q000235:genetics; D002450:Cell Communication / Q000502:physiology*; D006224:Cricetinae; D003412:Cricetulus; D007700:Kinetics; D017434:Protein Structure, Tertiary / Q000235:genetics; D017384:Sequence Deletion; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis
C074260:CDH3 protein, Xenopus; D015820:Cadherins; D029867:Xenopus Proteins