We demonstrate a reliable method for mapping conventional loci and obtaining meiotic linkage data for the ciliated protozoan Tetrahymena thermophila. By coupling nullisomic deletion mapping with meiotic linkage mapping, loci known to be located on a particular chromosome or chromosome arm can be tested for recombination. This approach has been used to map three isozyme loci, EstA (Esterase A), ...

O S M O T I C (os) mutants of N . crassa are those whose growth is inhibited by high osmolalities. The usual operational definition is inhibition of growth of the mutant strains by the addition of 4% NaCl to the growth medium (PERKINS 1959). Prior to the present investigation, a group of os mutants had been mapped on linkage group IR, at approximately 90 map units from the centromere (PERKINS 1...

The unusual Chlamydomonas linkage group XIX-called the uni linkage group for the uni mutants that lack one of the paired flagellae of wild-type cells--has been reported to be physically located exclusively at the basal bodies. To learn whether the structure of genes on this linkage group differs from the structure of nuclear genes in this organism, we determined the primary structure of a gene ...

In soybean, an environmentally stable male sterility system is vital for making hybrid seed production commercially viable. Eleven male-sterile, female-fertile mutants (ms1, ms2, ms3, ms4, ms5, ms6, ms7, ms8, ms9, msMOS, and msp) have been identified in soybean. Of these, eight (ms2, ms3, ms5, ms7, ms8, ms9, msMOS, and msp) have been mapped to soybean chromosomes. The objectives of this study w...