The PLACE database is a collection of nucleotide sequence motifs found in plant cis-acting regulatory DNA elements. Motifs were extracted from previously published reports on genes in vascular plants. In addition to the motifs originally reported, their variations in other genes or in other plant species in later reports are also compiled. Documents for each motif in the PLACE database contain, in addition to a motif sequence, a brief definition and description of each motif, and relevant literature with PubMed ID numbers and GenBank accession numbers where available. Users can search their query sequences for cis-elements using the Signal Scan program at our web site. The results will be reported in one of the three forms. Clicking the PLACE accession numbers in the result report will open the pertinent motif document. Clicking the PubMed or GenBank accession number in the document will allow users to access to these databases, and to read the abstract of the literature or the annotation in the DNA database. This report summarizes the present status of this database and available tools. The PLACE database is a compilation of motifs found in plant cis-acting regulatory DNA elements, extracted from previously published reports, and also from article reviews on the regulatory regions of various plant genes. The originally reported motifs, as well as their variations in other genes or other plant species in later reports, are included. The PLACE database also includes some motifs in non-plant cis-elements in the hope that this may assist in finding plant homologues. A unique identifier (ID) is assigned to each motif. Early entries have IDs identical to the motif names, which appeared in the reports. As many variations of different motifs appeared, a unique ID to the PLACE database was assigned by the following format: [name of cis-element motif (or trans-acting factor binding site)][plant scientific name (in initials)] and [gene name]. For example, LTRE (low temperature responsive element) found in Arabidopsis thaliana lti78 gene was registered as LTREATLTI78 in the PLACE database. Furthermore identical motif sequence(s) with the same function found in other gene(s) and/or in other plant species are described in the DE field of the document for LTREATLTI78. The motif names commonly used, or their synonyms, are also described in the same DE field. A unique accession number (AC) is assigned to a motif sequence. The format is: S (for site) followed by a six-digit number. This number is strictly associated with a particular registered sequence. When later reports indicate a portion of the registered sequence to be a true motif, a new accession number will be assigned to the shorter motif, and the DE field revised accordingly. Up to seven references will be included in a document. Additional references will be incorporated after deleting others. The first report on the motif and review articles will normally be retained. Deleted reference(s) may be cited in DE field when space is available. We added PubMed ID and GenBank accession numbers toThe PLACE database is a collection of nucleotide sequence motifs found in plant cis-acting regulatory DNA elements. Motifs were extracted from previously published reports on genes in vascular plants. In addition to the motifs originally reported, their variations in other genes or in other plant species in later reports are also compiled. Documents for each motif in the PLACE database contain, in addition to a motif sequence, a brief definition and description of each motif, and relevant literature with PubMed ID numbers and GenBank accession numbers where available. Users can search their query sequences for cis-elements using the Signal Scan program at our web site. The results will be reported in one of the three forms. Clicking the PLACE accession numbers in the result report will open the pertinent motif document. Clicking the PubMed or GenBank accession number in the document will allow users to access to these databases, and to read the abstract of the literature or the annotation in the DNA database. This report summarizes the present status of this database and available tools. The PLACE database is a compilation of motifs found in plant cis-acting regulatory DNA elements, extracted from previously published reports, and also from article reviews on the regulatory regions of various plant genes. The originally reported motifs, as well as their variations in other genes or other plant species in later reports, are included. The PLACE database also includes some motifs in non-plant cis-elements in the hope that this may assist in finding plant homologues. A unique identifier (ID) is assigned to each motif. Early entries have IDs identical to the motif names, which appeared in the reports. As many variations of different motifs appeared, a unique ID to the PLACE database was assigned by the following format: [name of cis-element motif (or trans-acting factor binding site)][plant scientific name (in initials)] and [gene name]. For example, LTRE (low temperature responsive element) found in Arabidopsis thaliana lti78 gene was registered as LTREATLTI78 in the PLACE database. Furthermore identical motif sequence(s) with the same function found in other gene(s) and/or in other plant species are described in the DE field of the document for LTREATLTI78. The motif names commonly used, or their synonyms, are also described in the same DE field. A unique accession number (AC) is assigned to a motif sequence. The format is: S (for site) followed by a six-digit number. This number is strictly associated with a particular registered sequence. When later reports indicate a portion of the registered sequence to be a true motif, a new accession number will be assigned to the shorter motif, and the DE field revised accordingly. Up to seven references will be included in a document. Additional references will be incorporated after deleting others. The first report on the motif and review articles will normally be retained. Deleted reference(s) may be cited in DE field when space is available. We added PubMed ID and GenBank accession numbers to