Development of the Japanese Medaka as a Laboratory Animal with Genetic and Environmental Control.

The following results obtained from our 2 years' study:1. The two dimensional electrophoreticanalysis of muscle and egg proteins successfully used for species of the genus2. The hatching enzyme of The Medaka was found to consist of two different proteases，HCE and LCE，and the two components were purified and characterized. 3. the muscle lds - a_4 and - b_4 isozymes of4. Medaka已被确定并被临时修改。5. regard to the hybrid sterility in the genus Oryzias. 5. the method to obtain continuous bands inchromosomes was established using trypsin - Giemsa as well as BrdU method. 6. The C banding and NORbanding methods were successfully applied for the chromosomes of O. curvinotus and O. minutillusB。7. Japanese Medaka was definitively confirmed to consist of 4 major populations. The Nei'sgenetic distance was estimated to be 0.3 to 0.5，8.这是一个fairly large value for intraspecies variation. 8. attempt was started and continuedto establish inbred strains in d - rr9. The method for genetic monitoring of The inbred strains thus far obtained10. the new 6 mutations使用polymorphisms with regard to 8 marker enzymes。at the b allele were isolated from f_1 progeny obtained by the Medaka specific-locus test systemthat has been developed by ourselves using gamma-rays and ethylnitrosouresa potent chemical mutagen. In these new mutantsthe extent of melanizatin of eyes body surface was less than that in the mutants at the b and b^pPoci, indicating that all the 6 mutations newly isolated were recessive even to b and b<@1p>@D1，possibly the bottom allele at the b locus. 11. the MLR assay procedure was开发使用ingleukocytes of the goldfish12. the spontaneous as well as chemically induced the spontaneous as chemically inducedtumors in the Medaka were characterized from a view point of comparative oncology。

The following results were obtained from our 2 years' study :1. The two dimensional electrophoretic analysis of muscle and egg proteins was successfully used for identification of species of the genus oryzias. 2. The hatching enzyme of the Medaka was found to consist of two different proteases, HCE and LCE, and the two components were purified and characterized. 3. The muscle LDH-A_4 and ーB_4 isozymes of the Medaka were purified and partially characterized. 4. Several possibilities were pointed out with regard to the hybrid sterility in the genus Oryzias. 5. The method to obtain continuous bands in chromosomes was established using trypsinーGiemsa as well as BrdU method. 6. The C banding and NOR banding methods were successfully applied for the chromosomes of O. curvinotus and O. minutillusB. 7. The Japanese Medaka was definitively confirmed to consist of 4 major populations. The Nei's genetic distance was estimated to be 0.3 to 0.5, which was a fairly large value for intraspecies variation. 8. The attempt was started and continued to establish inbred strains in dーrr, Da and Korean Medaka. 9. The method for genetic monitoring of the inbred strains thus far obtained was established by the use of polymorphisms with regard to 8 marker enzymes. 10. The new 6 mutations at the b allele were isolated from F_1 progeny obtained by the Medaka specific-locus test system that has been developed by ourselves using gamma-rays and ethylnitrosoures, a potent chemical mutagen. In these new mutants, the extent of melanizatin of eyes body surface was less than that in the mutants at the b and b^p Poci, indicating that all the 6 mutations newly isolated were recessive even to b and b<@1p>@D1, possibly the bottom allele at the b locus. 11. The MLR assay procedure was developed using leukocytes of the goldfish, and was started being applied for the Medaka. 12. The spontaneous as well as chemically induced tumors in the Medaka were characterized from a view point of comparative oncology.