General
Feature editor is an editor with which you can modify the content of a feature. You can modify:
- feature type
- sequence
- qualifiers (add, modify and delete)
Normally the Feature editor does not let you edit source features. Unless a sequence is artificial, source features reflect a sequence’s organism and length fields. Those fields are updated in the process of editing the sequence in the Sequence editor.
CDS (coding sequence)
The CDS feature defines the coding region of the sequence. If such a feature exists, the coding region of the sequence can be translated. The translation process generates a new sequence. The sequence identifiers of the generated sequences immediately follow the identifier of the original. For example, if the original sequence is number 3, then the generated protein sequences have consecutive numbers starting with 4.
Adding a CDS to a sequence requires a renumbering of the sequences whose sequence identifier is higher then the identifier of the sequence in question. This operation can be lengthy, if a huge number of sequences has to be adjusted in the database. It is advisable to generate sequences as early as possible. The removal of the original sequence, or the CDS feature in turn, removes the generated sequence.
BiSSAP lets you decide whether to translate that sequence at the same time as you save the feature. Note that a project without all generated sequences is incomplete and cannot be exported.
For details see Translations.
Qualifiers
The qualifiers assigned to a feature are visible in the table at the bottom of the Feature Editor. The first column contains the name and the second column contains a value.
To add a qualifier, first select the qualifier name and then enter the value. The name is chosen from the list of allowed qualifiers, which depends on the feature key. Until you select the feature key, you cannot enter qualifiers. If you change the feature key, the qualifiers not allowed for that feature key are marked red. They will be removed during the save operation. If you revert to the previous feature key before you save, the red marking should disappear and the qualifiers should be accepted again.
To edit a qualifier, double-click it in the table. You can change its name and value in the text fields above the qualifier table.
The qualifiers list is validated in two ways. BiSSAP checks that the qualifiers assigned to a feature are actually allowed for that feature. Where possible, qualifier values are checked by means of regular expressions to establish whether they are in the correct form.
Any wrong qualifiers are removed from the list while saving.
Source
The source feature can be modified only in the case of an Artificial sequence.