SAWANT M. S.; ZHANG Shicui; WANG Qingyin
Zebrafish (Danio rerio) genetic screens allow isolation of a wide array of problems in vertebrate biology. The effects of base analogues 5-bromouracil and 6-aminopurine on the development of zebrafish embryos are reported for the first time in this study. The early development of the zebrafish embryos was little affected by 5-bromouracil and 6-aminopurine, while the late development (organogenesis) was significantly impaired. Embryos exposed to 5-bromouracil mainly showed curled tail, wavy body, golden pigmentation and the mouth with protruding lower jaw. 6-aminopurine-treated embryos had defective anterior structures, curled tails and wavy body. RAPD analysis showed that the majority of 5-bromouracil- and 6-aminopurine-treated larvae and fish shared banding patterns in common with the control, suggesting that most mutagenesis induced by these agents are point mutations. However, some fish derived from 5-bromouracil-treated embryos had golden (gol) pigmentation; and RAPD analysis revealed that their band patterns differed from those of the control.Possibly, 5-bromouracil can occasionally cause relatively extensive changes in the fish genome. The results of this study may provide valuable help for detailed studies of mutagenesis.
The phage Mu mom gene controls an unusual DNA modification. Expression of the mom function requires an active host (dam+) DNA adenine methylase [S-adenosyl-L-methionine:DNA (6-aminopurine)-methyltransferase]; in dam- hosts, Mu development is normal except that the viral DNA does not undergo the mom modification. The present communication compares transcription of the mom gene in dam+ versus dam- cells. 32P-labeled probes were prepared by nick-translation of a purified mom gene-containing rest...
Saini, Raman; Jaiwal, Pawan K
The efficiency of Vigna mungo L. Hepper transformation was significantly increased from an average of 1% to 6.5% by using shoot apices excised from embryonic axes precultured on 10 microM benzyl-6-aminopurine (BAP) for 3 days and wounded prior to inoculation in Agrobacterium tumefaciens strain EHA105 carrying the binary vector pCAMBIA2301, which contains a neomycin phosphotransferase gene (nptII) and a beta-glucuronidase (GUS) gene (gusA) interrupted by an intron. The transformed green shoots that were selected and rooted on medium containing kanamycin, and which tested positive for nptII gene by polymerase chain reaction, were established in soil to collect seeds. GUS activity was detected in whole T(0) shoots and T(1) seedlings. All T(0) plants were morphologically normal, fertile and the majority of them transmitted transgenes in a 3:1 ratio to their progenies. Southern analysis of T(1) plants showed integration of nptII into the plant genome.
Giovanni Orlando Cancino-Escalante
Full Text Available In this study plant materials were selected in 53 farms belonging to four growers associations of blackberry in the municipalities of Pamplona and Chitagá (North of de Santander, Colombia. Nodal segments were used as initial explants of R. glaucus. For the establishment stage Murashige and Skoog, 1962 (MS media was used and, supplemented with of gibberellic acid (GA3 (0.0 -0.1 mg/L and 6-aminopurine (BAP (0.0 -2.0 mg/L; for the multiplication stage MS was supplemented with GA3 (0.0 -0.03 mg/L and BAP, (0.0 -2.5 mg/L and for the rooting stage MS was supplemented with acid indolbutirico (0.0 -1.0 mg/L. From the data generated during the three stages, an experimental design of incomplete blocks was randomly applied and the treatments averages were statistically analyzed using the Tukey Test. The results indicated average rates of contamination (16.5-49.7 %, multiplication (3.8-4.3 shoots/explant and in vitro rooting (3.3-4.3 roots/plant for the different evaluated materials. These results, achieved first in the Northeastern region of Colombia, are important in that they will feature selected materials available for blackberry growers in the region.