Subfamily

Structure

Features

Activities

NMR

Crystal

DD

Fas DD

FADD DD

TNFR1 DD

P75 DD

IRAK4 DD

RAIDD DD

Variation exist in length and direction of helices

Sequence homology low

Homotypic interactions

Form homodimers

Use to assemble signal complexes intracellularly for activation of caspase and NF-кB

DED

FADD DED

PEA-15 DED

MC159 DED1

MC159 DED2

H2 residues form a hydrophobic patch

E/D-RxDL motif form a conserved hydrogen-bonded charge

Found on caspases and adapters

Induce apoptosis (DED containing caspase)

NF-кB signalling

Induce or inhibit caspase activation

CARD

RAIDD CARD

ICEBERG CARD

Apaf-1

H1 either bent or broken into H1a and H1b helices

Have polarized surface for interactions.

Apoptosis

Cytokine processing

Immune defense

NF-кB activation

PYD

NALP1 PYD

ASC PYD

NONE

H3 is altered replace by flexible loop

Probable caspase activation

Function not really understood