ISSN:
1573-4943
Keywords:
Small heat shock protein
;
molecular chaperone
;
α-crystallin domain
;
oligomeric structure
;
conserved residue
;
ANS binding
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract To understand the role of the only universally conserved hydrophobic residue among all the members of the sHsp family, this extremely well conserved Leu122 residue in Hsp16.3 was replaced by valine, alanine, asparigine, or aspartate residues. Only very small amounts of the L122D and L122N mutant Hsp16.3 proteins were expressed in the transformed E. coli; however, both the L122V and L122A were readily expressed. The L122V and L122A mutant proteins had similar oligomeric structures to the wild-type protein at room temperature. Examination of the L122A mutant protein by native pore gradient PAGE and CD spectroscopy, however, revealed a smaller oligomeric size and different secondary structure at 37°C. Both L122V and L122A mutant proteins exhibited significantly lowered chaperone activities. Observations reported here suggest a very important role of this only universally conserved Leu residue in both the formation of specific oligomeric structures and the molecular chaperone activities of Hsp16.3.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007003631120
Permalink