ISSN:
0886-1544
Keywords:
fluorescent nucleotide analogs
;
methylanthraniloyl ATP
;
anthraniloyl ATP
;
Chlamydomonas
;
axonemal mutants
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Substrate analogs are useful for studying the structures of active sites and for distinguishing between similar enzyme activities. Fluorescent ribose-modified ATP analogs were used to investigate the functional differences between dynein ATPases. These analogs reactivate (support the movement of) sea urchin sperm axonemes, yet they do not reactivate wild-type Chalmydomonas axonemes. Surprisingly, the analogs reactivate the axonemes of mutants completely missing the outer arm dyneins. Competition experiments using ATP and these analogs provide strong evidence that the analogs bind to all dynein active sites but fail to release a subset of dyneins from rigor. We suggest that this subset of Chlamydomonas outer arm dyneins unable to use the analogs remains in rigor in the presence of the analogs and paralyzes the axoneme. © 1994 Wiley-Liss, Inc.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cm.970270207
