annotation efforts as well as improving the understanding of the regulation
of gene expression. A knowledge of the features of promoter elements
surrounding putative genes would aid in the prediction
of the type of con-
ditions and/or tissues in which the putative gene might be expressed,
thereby directing the search for confirmation of the gene and its structure
to the appropriate target tissue. The selection
of the transcription start
site, specificity, and rate is controlled by elements of the promoter that can
be thousands of nucleotides from the actual transcription start site. A
number
of databases that contain cis-acting sequences are available. A new
plant specific database, PlantPromDB, release 2001.01, contains 305
entries
including 71, 220, and 14 promoters for RNA polymerase II from monocot,
dicot, and other plants, respectively (Shahmuradov et al., 2003). A second
database, Plant CARE (Lescotet et al., 2002)
contains plant cis-regulatory ele-
ments, enhancers, and repressors. This database currently contains 417
cis-
regulatory elements, 150 of which are from monocots, 263
from dicots, and
4 from conifers derived from 160 individual promoters from higher-plant
genes.
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