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. If you right-click on the sequence in the Sequence Browser and select Generate protein, the translation process generates a new sequence that is appended at the end of the current list of sequences. For example, if the CDS feature belongs to sequence number 3 and the current list contains 10 sequences, then the generated protein sequence will be number 11.
The removal of the original sequence, or the CDS feature in turn, removes the generated sequence.
Once you decide to generate the sequence listing, if the project contains CDS features but the corresponding amino acid sequences have not been generated, you will the option to generate or not the amino acid sequences derived from the CDS information.
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.