Identification of zein structural genes in the maize genome. [Maize proteins]

Conference · Sun Jan 01 04:00:00 EST 1978

OSTI ID:6646490

Burr, B

Zein is the major storage protein in maize endosperm and is deficient in the amino acids lysine and tryptophan, the amino acids generally limiting in cereal grains. If the two subunits of zein were each encoded by a single gene, it is possible to envisage a program in which altered gene products containing these two amino acids could be selected. Since zein constitutes such a large proportion of the total protein, substitutions of rare amino acids into zein will be reflected in the overall amino acid composition of the kernel. At the moment we do not know how many genes for zein there are, nor do we know where they are located in the genome. In our approach to this question we have purified the messenger RNAs for the two zein polypeptide chains free from all other species of RNA. The mRNAs are polyadenylated, have a cap structure at their 5' terminus, and contain slightly less than 50% noncoding sequences. Their average length is 1.1 kilobases and we assume they are monocistronic. Using reverse transcriptase and DNA polymerase we prepared double-stranded DNA transcripts of the messages. These were inserted into the bacterial plasmid pMB9 and used to transfect E. coli. A number of clones carrying nearly full length inserts have been selected for study. These recombinant DNA molecules are being used as probes to accurately count the number of zein genes in the maize genome, check for amplification, and determine the chromosomal location of the genes.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• Sponsoring Organization: USDOE
• DOE Contract Number: EY-76-C-02-0016
• OSTI ID: 6646490
• Report Number(s): BNL-24704; CONF-780955-2; IAEA-SM-230/72
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
550400 -- Genetics
553000 -- Agriculture & Food Technology
560303 -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
60 APPLIED LIFE SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACIDS
AZOLES
BIOSYNTHESIS
CARBOXYLIC ACIDS
CEREALS
CHEMICAL COMPOSITION
ENDOSPERM
GENETIC CONTROL
GRAMINEAE
GRASS
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INDOLES
LYSINE
MAIZE
MESSENGER-RNA
MOLECULAR BIOLOGY
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PEST CONTROL
PLANT TISSUES
PLANTS
PROTEINS
PYRROLES
RNA
SYNTHESIS
TRYPTOPHAN