Feature Table Information

   The feature table contains information about genes and gene products, as well as regions of biological significance reported in the sequence. The feature table contains information on regions of the sequence that code for proteins and RNA molecules. It also enumerates differences between different reports of the same sequence, and provides cross-references to other data collections, as described in more detail below.

Feature Keys

   The first column of the feature descriptor line contains the feature key. The list of valid feature keys is shown below.

Feature Location

   The second column of the feature descriptor line designates the location of the feature in the sequence. Several conventions are used to indicate sequence location.
    Base numbers in location descriptors refer to numbering in the entry, which is not necessarily the same as the numbering scheme used in the published report. The first base in the presented sequence is numbered base 1. Sequences are presented in the 5 to 3 direction.
    Location descriptors can be one of the following:

1. A single base
2. A contiguous span of bases
3. A site between two bases
4. A single base chosen from a range of bases
5. A single base chosen from among two or more specified bases
6. A joining of sequence spans
7. A reference to an entry other than the one to which the feature belongs (i.e., a remote entry), followed by a location descriptor referring to the remote sequence
8. A literal sequence (a string of bases enclosed in quotation marks)

   A site between two residues, such as an endonuclease cleavage site, is indicated by listing the two bases separated by a carat (e.g., 23^24).
    A single residue chosen from a range of residues is indicated by the number of the first and last bases in the range separated by a single period (e.g., 23.79).
    The symbols < and > indicate that the end point of the range is beyond the specified base number.
    A contiguous span of bases is indicated by the number of the first and last bases in the range separated by two periods (e.g., 23..79).
    Operators are prefixes that specify what must be done to the indicated sequence to locate the feature. The following are the operators available, along with their most common format and a description.

complement (location)

The feature is complementary to the location indicated. Complementary strands are read 5 to 3.

join (location, location, .. location)

The indicated elements should be placed end to end to form one contiguous sequence.

order (location, location, .. location)

The elements are found in the specified order in the 5 to 3 direction, but nothing is implied about the rationality of joining them.

group (location, location, .. location)

The elements are related and should be grouped together, but no order is implied.

one-of (location, location, .. location)

The element can be any one, but only one, of the items listed.

replace (location, location)

The first location indicated should be replaced by the sequence from the second location; used for insertions, deletions, and variants.

Feature Qualifiers

   Qualifiers provide additional information about features. They take the form of a slash (/) followed by a qualifier name and, if applicable, an equal sign (=) and a qualifier value. Qualifiers convey many types of information. Therefore, their values can take free text, controlled vocabulary, enumerated values, reference numbers, sequences, or feature labels.
    The following is a list of valid feature qualifiers.

Feature Table Example 1

     CDS             5..1261

                     /product="alpha-1-antitrypsin precursor"

                     /map="14q32.1"

                     /gene="PI"

     tRNA            1..87

                     /note="Leu-tRNA-CAA (NAR: 1057)"

                     /anticodon=(pos:35..37,aa:Leu)

     mRNA            1..>66

                     /note="alpha-1-acid glycoprotein mRNA"

     transposon      <1..267 /note="insertion element IS5" misc_recomb 105^106 /note="B.subtilis DNA end/IS5 DNA start" conflict replace(258..258,"t") /citation="[2]" 

Feature Table Example 2 -- joining entries

LOCUS       HUMPGAMM1    3688 bp ds-DNA             PRI       15-OCT-1990

DEFINITION  Human phosphoglycerate mutase (muscle specific isozyme) (PGAM-M)

            gene, 5' end.

ACCESSION   M55673 M25818 M27095

KEYWORDS    phosphoglycerate mutase.

SEGMENT     1 of 2

  .

  .

FEATURES             Location/Qualifiers

     CAAT_signal     1751..1755

                     /gene="PGAM-M"

     TATA_signal     1791..1799

                     /gene="PGAM-M"

     exon            1820..2274

                     /number=1

                     /EC_number="5.4.2.1"

                     /gene="PGAM-M"

     intron          2275..2377

                     /number=1

                     /gene="PGAM2"

     exon            2378..2558

                     /number=2

                     /gene="PGAM-M"

  .

  .

//

LOCUS       HUMPGAMM2     677 bp ds-DNA             PRI       15-OCT-1990

DEFINITION  Human phosphoglycerate mutase (muscle specific isozyme) (PGAM-M),

            exon 3.

ACCESSION   M55674 M25818 M27096

KEYWORDS    phosphoglycerate mutase.

SEGMENT     2 of 2

  .

  .

FEATURES             Location/Qualifiers

     exon            255..457

                     /number=3

                     /gene="PGAM-M"

     intron          order(M55673:2559..>3688,