Specific neuroanatomical changes in chemosensory mutants of the nematodeCaenorhabditis elegans

摘要

AbstractEight of nineteen chemotactic mutants of the nematodeCaenorhabditis eleganshave morphological defects in the sensory endings of neurons at the tip of the head. The mutants were obtained as worms swimming away from attractant or found amongst male potency mutants or mutants exhibiting erratic behavior. The nineteen mutants fall into at least twelve complementation groups. Mutants E1034 and E1035, alleles ofche‐1, show morphological alterations in the sensory endings of amphidial neurons and inner labial type 2 neurons, both prospective chemosensory neurons. Both mutants contain noncomplementing ts sterile mutations linked to the chemosensory mutation. E1066 shows abnormalities in all the sheath cells associated with the sensory neurons and in the bundling pattern of the amphidial neurons. El 126 is structurally abnormal only in the sensory endings of inner labial type 2 neurons, supporting a chemosensory role for these neurons. E1033(cke‐2)and El 124(cke‐3)cause defects in the ciliary structure of all but one type of ciliated sensory neuron in the head. E1062 is grossly defective in head structure and the structure of the male copulatory organ, suggesting these opposite ends of the nematode rich in sensory structures share gene functions in embryogenesis. Our study illustrates the possibilities for genetic dissection of the development of a small set of nerves in a simple org