InterPro domain: IPR006702

This domain is found mainly in plant proteins known as Casparian strip membrane proteins (CASPs). CASPs are four-membrane-span proteins that mediate the deposition of Casparian strips in the endodermis by recruiting the lignin polymerization machinery. Interestingly, the CASP first extracellular loop was found conserved in euphyllophytes but absent in plants lacking Casparian strips [ 1 , 2 ].

1. A novel protein family mediates Casparian strip formation in the endodermis. Nature
2. Functional and evolutionary analysis of the CASPARIAN STRIP MEMBRANE DOMAIN PROTEIN family. Plant Physiol. 473, 380-3