Gene topography and function. I. Gene expression in germinating conidia of Neurospora crassa.

In an attempt to find clues for the significance of the gene ordering along the eukaryotic chromosome, a system consisting of germinating conida of Neurospora crassa was studied. Thirteen enzyme activities corresponding to genes widely distributed on five chromosomes were determined in dormant and in germinating conidia. Ten of these enzymes showed lower activities in the resting state, and the time patterns of their increase were determined during germination. The results obtained do not support a scheme of sequential expression of genes during the emergence from dormancy as a counterpart of the sequence of the corresponding genes along the chromosome. Two of the loci studied were analyzed both in the normal (wild-type) ordering and in a translocated position in which the two genes are located in an inverted order respective to the centromere and farther apart from it. The altered order of the genes did not influence significantly the time and pattern of increase in the activities of the corresponding enzymes.