Developmental induction of glutaminase in primary cultures of cerebellar granule cells.
Glutaminase mRNA levels increased over 3-fold relative to total RNA, poly(A)+ RNA, and beta-actin mRNA in neonatal rat cerebellar granule cells as the cells differentiated between days 3 and 8 in culture. In contrast, mRNA levels of another glutamate cycle enzyme, glutamine synthetase, remained constant. Glutaminase protein levels increased per cell more than 2-fold between days 3 and 8, and at least 3-fold by day 10 in these cells. The total amount of glutamate per cell increased about 40% during this period. Glutaminase induction paralleled the development of Ca2+-dependent glutamate release, and the formation of neurites, synaptic vesicles, and synapses. The induction of glutaminase in developing granule cells is consistent with a special role for glutaminase in the synthesis of neurotransmitter glutamate.
Thomas
J W
JW
Laboratory of Molecular Biology, National Institute of Neurological Communicative Disorders and Stroke, Bethesda, MD 20892.
Novelli
A
A
Tao-Cheng
J H
JH
Henneberry
R
R
Smith
H H
HH
Banner
C
C
D000818:Animals; D002118:Calcium / Q000502:physiology; D002454:Cell Differentiation; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology / Q000201:enzymology* / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D005972:Glutaminase / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D005971:Glutamates; D012333:RNA, Messenger; D018698:Glutamic Acid; D005972:Glutaminase; D002118:Calcium