Protein Layout — select a broad structural category (e.g. R-SNARE, Qa-SNARE, HABC domain). This filters the available domain names.

Domain Name — select a specific domain (e.g. VAMP2, Syntaxin-1). Choosing a layout first narrows the list. If left empty, all domain names within the selected layout are included.

Domain Group rank — choose a classification level (e.g. subfamily, clade) to browse domain groups at that granularity.

Domain Group list — select one or more groups at the chosen rank to filter sequences belonging to those groups.
Hold Ctrl to select multiple non-consecutive entries. Hold Shift to select a range.
To deselect an entry, hold Ctrl and click it again.
If no group is selected, all groups within the chosen rank are included.