Premium
Dimerization properties of a Xenopus laevis kinesin‐II carboxy‐terminal stalk fragment
Author(s) -
De Marco Valeria,
de Marco Ario,
Goldie Kenneth N,
Correia John J,
Hoenger Andreas
Publication year - 2003
Publication title -
embo reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.584
H-Index - 184
eISSN - 1469-3178
pISSN - 1469-221X
DOI - 10.1038/sj.embor.embor884
Subject(s) - stalk , xenopus , circular dichroism , coiled coil , helix (gastropod) , chemistry , biology , stereochemistry , biochemistry , gene , ecology , snail , horticulture
We have analysed the structural and physical properties of the carboxy‐terminal stalk region of a kinesin‐II, Xenopus kinesin‐like protein 3A/B (Xklp3A/B), which we showed to be essential for heterodimerization in a previous work (De Marco et al ., 2001). We expressed the corresponding A‐stalk and B‐stalk fragments and investigated their modes of interaction by analytical ultracentrifugation (AUC), circular dichroism spectroscopy, denaturation assays and electron microscopy. Co‐expression of the A‐stalk and B‐stalk produced the properly folded, hetero‐dimeric coiled coil at high yields. The dimeric nature of the complex was confirmed by AUC. We also found that the isolated A‐stalk fragment forms a stable helix by itself and shows a significant tendency towards homodimer and higher‐order complex formation. In the absence of the corresponding A‐stalk fragment, the isolated B‐stalk fragment remains partially unfolded, which suggests that the A‐stalk provides a template structure for the B‐stalk in order to recompose the complete heterodimeric coiled coil.