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SUMMARY OF DR. NIRENBERG'S RESEARCH

Dr. Nirenberg and his coworkers studied the steps that relate
DNA, RNA, and protein. They showed that messenger RNA is required for
protein synthesis and that synthetic oligo - and polyribo nucleotides
have messenger activity. Over a five year period they deciphered the
genetic code.

Dr. Nirenberg then began to work in the field of developmental
neurobiology. He and his colleagues established many clonal lines of
mouse neuroblastoma cells and somatic hybrid cells that express neural
properties in culture, and cell lines were found that form synapses
in culture with striated muscle cells. The cell lines were given to
many investigators and now are widely used as model systems for
studies in neurobiology and related fields. Nirenberg and his
coworkers found that synaptogenesis and other neural properties are
regulated by cAMP. Prolonged elevation of cellular cAMP levels shifts
the cells to a more differentiated state that enables the cells to
form synapses. cAMP was found to activate the expression of a gene
for an L-type voltage-sensitive calcium channel a-1 subunit that is
required for stimulus-secretion coupling at synapses. The calcium
channel gene was cloned and sequenced and factors that regulate the
expression of this calcium channel gene, which have long term effects
on the efficiency of transynaptic communication, are being studied
currently.

In addition, Dr. Nirenberg and his coworkers recently have cloned
and sequenced Drosophila or mouse genomic DNA or cDNA for 10 novel
homeobox genes or Pou box-homeobox genes. These genes code for
proteins that bind to DNA and thereby regulate gene expression.

Current studies center on defining the functions of these genes during
the development of the nervous system.
Dr. Nirenberg has received many honors and awards including the

Nobel Prize in Medicine.