A new ‘paralyzed’ flagella mutant, OC‐10, in Chlamydomonas reinhardtii (Volvocales, Chlorophyceae) that can be reactivated with adenosine triphosphate

Abstract

SUMMARYA new ‘paralyzed’ mutant. OC–10, was isolated in Chlamydomonas reinhardtii Dangeard. OC‐10 cannot swim and generally shows very little flagellar movement. However, when OC‐10 was demembranated, axonemal motility was reactivated in the presence of adenosine triphosphate (ATP) or adenosine diphosphate (ADP). The beating form of the reactivated axonemes was almost the same as that of the wild‐type axonemes. Flagellar regeneration of OC‐10 was slower than that of the wild‐type. Electron microscopic examination showed no abnormality in OC‐10 flagella, but SDS/PAGE revealed that mobility of a flagellar membrane protein was changed and a few bands disappeared in OC‐10 flagella, When the mutant was crossed to wild‐type to form temporary dikaryon cells with 4 flagella, OC‐10 flagella did not regain motility. Tetrad analysis of crosses between OC–10 and wild‐type demonstrated a 1:1 segregation on the basis of flagellar motility. From these results, we suppose that OC‐10 may be limited in ATP availability inside the flagella, or altered in flagellar membrane proteins important for motility.