Differential gene expression in Neurospora crassa cell types: heterogeneity and amplification of rRNA genes. Progress report, July 1980-June 30, 1981

Technical Report · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6299449

Dutta, S K

The significant results obtained during 1980-1981 year of the current research program are as follows: I. Studies on heterogeneity of multiple copies of rDNAs from N. crassa cell types are being continued, such as: (1) Autoradiographs of Southern transfers of EcoR/sub 1/ restricted fragments of nuclear DNA from conidia, germinated conidia (sprouts) and mycelia of N. crassa were compared after hybridization with /sup 32/P-rDNA probe. The nuclear DNA of two hours sprout and of 16 hours mycelia gave similar hybridization patterns with EcoR/sub 1/ digest, but no such hybridization pattern was evident in conidial DNA digest; (2) Procedure for concentration of rDNAs from Neurospora species and cell types was standardized; restriction analysis of purified rDNAs is being done; (3) 35S total rDNA clone, 17S rDNA clone and 26S rDNA subclone are being used to see gross differences in the precursor rRNAs of different cell types; (4) Comparison of DNA:DNA homologies of rRNA genes with different Neurospora species. II. Post-mitochondrial DNAs of N. crassa are found to be rDNA-like and were further characterized by electron microscopic studies and are found to be approximately twice the size of SV-40 DNAs. These N. crassa post-mitochondrial DNAs hybridized with /sup 32/P-labeled N. crassa nuclear DNAs. III. Previous studies on differential RNase sensitive DNA polymerase activity in N. Crassa cell types and on evolution of sexual morphogenesis in the genus Neurospora are completed and published. RNase sensitive DNA polymerase activity is found to be in the post-mitochondrial fraction. Heterothallism in the genus Neurospora is evolved from homothallism.

• Research Organization: Howard Univ., Washington, DC (USA)
• DOE Contract Number: AS05-76EV04182
• OSTI ID: 6299449
• Report Number(s): DOE/EV/04182-T1; ON: DE81026730
• Country of Publication: United States
• Language: English

Related Subjects

550401* -- Genetics-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL VARIABILITY
DAYS LIVING RADIOISOTOPES
DNA
ELECTRON MICROSCOPY
FUNGI
GENETIC VARIABILITY
HYBRIDIZATION
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MICROSCOPY
NEUROSPORA
NUCLEI
NUCLEIC ACIDS
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PLANTS
RADIOISOTOPES
RESEARCH PROGRAMS
RNA
TRACER TECHNIQUES