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H Dooner

Publications and source records attributed to H Dooner.

10 recordsLinked to original sources
PubMed1997

Molecular cloning and characterization of ADP-glucose pyrophosphorylase cDNA clones isolated from pea cotyledons.

Three ADP-glucose pyrophosphorylase (ADPG-PPase) cDNA clones have been isolated and characterized from a pea cotyledon cDNA library. Two of these clones (Psagps1 and Psagps2) encode the small subunit of ADPG-PPase. The deduced amino acid sequences for these two clones are 95% identical. Expression of these two genes differs in that the Psagps2 gene shows comparatively higher expression in seeds relative to its expression in other tissues. Psagps2 expression also peaks midway through seed development at a time in which Psagps1 transcripts are still accumulating. The third cDNA isolated (Psagp11) encodes the large subunit of ADPG-PPase. It shows greater selectivity in expression than either of the small subunit clones. It is highly expressed in sink organs (seed, pod, and seed coat) and undetectable in leaves.

Amino Acid Sequence↗
PubMed1993

Arabidopsis requires polyunsaturated lipids for low-temperature survival.

Mutants of Arabidopsis that contain reduced levels of polyunsaturated fatty acids showed growth characteristics at 22 degrees C that were very similar to wild type. By contrast, at 12 degrees C, the mutants failed to undergo stem elongation during reproductive growth although they produced normal flowers and fertile seeds. After transfer to 6 degrees C, rosette leaves of the mutants gradually died, and the plants were inviable. These different responses of the mutant plants at 12 degrees C and 6 degrees C suggest that distinct functions may be affected at these two temperatures. The gradual development of symptoms at 6 degrees C and other lines of evidence argue against a general collapse of membrane integrity as the cause of the lethal phenotype. Rather, they indicate that the decrease in polyunsaturated membrane lipids may initially have relatively limited effects in disrupting cellular function.

Journal Article↗
PubMed1986

mRNA transcripts of several plant genes are polyadenylated at multiple sites in vivo.

We have analyzed the polyadenylation sites for the small subunit of ribulose bisphosphate carboxylase and chlorophyll a/b binding protein genes of Petunia (Mitchell) and the bronze gene of Zea mays. Sequence analysis of multiple cDNA clones revealed that polyadenylation of the transcripts occurred at either 2 or 3 sites for all three groups of genes. In the examples where 3 polyadenylation sites were detected, the middle site was the one predominantly used. Putative polyadenylation signals preceding the poly A tails diverged significantly from the animal consensus sequence AATAAA. In all the genes examined the first A residue in the poly A tail of the cDNA clones corresponded to an A residue in the homologous genomic sequence.

Base Sequence↗