COMPLEXITY OF STORAGE PROTEIN MESSENGER-RNA IN DEVELOPING CORN ENDOSPERM
Abstract
DNAs were synthesized by using zein mRNAs from normal and opaque-2 versions of the maize inbred W64A. The hybridization of zein mRNAs and cDNAs was more complex than that of ovalbumin mRNA and cDNA which was used as a standard. The hybridization of zein mRNAs and cDNAs occurred over 2.5 decades of R(,0)t and was best described by two kinetic components based on computer analysis using a least-squares procedure to analyze the data. Compared to the ovalbumin standard, the two components of the reaction involving mRNAs from the normal inbred had complexities of 200 and 3950 nucleotides. The complexity of these components was 338 and 3330 nucleotides for the reaction involving mRNAs from the opaque-2 mutant. When the hybrid formation of normal mRNA and cDNA was determined by hydroxylapatite chromatography rather than by S(,1) nuclease digestion, only one kinetic component was observed with a complexity of 270 nucleotides. By hybrid-arrested translation of normal mRNA with cDNA prepared from opaque-2 mRNA it was demonstrated that a portion of the reduced sequence complexity in the mutant was due to a reduction in the mRNAs for the 22000 molecular weight prezein proteins. By hybridizing the cDNAs to maize DNA we determined that the zein genes were present in 1-5 copies/haploid genome.
Degree
Ph.D.
Subject Area
Plant propagation
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.