Conserved Site

11-S seed storage protein, conserved site (IPR022379)

Short name: 11S_seedstore_CS

Description

Plant seed storage proteins, whose principal function appears to be the major nitrogen source for the developing plant, can be classified, on the basis of their structure, into different families. 11-S are non-glycosylated proteins which form hexameric structures [PMID: 2450746, PMID: 16666210]. Each of the subunits in the hexamer is itself composed of an acidic and a basic chain derived from a single precursor and linked by a disulphide bond. This structure is shown in the following representation.

                   +-------------------------+
                   |                         |
        xxxxxxxxxxxCxxxxxxxxxxxxxxxxxxxxxxNGxCxxxxxxxxxxxxxxxxxxxxxxx
        |------Acidic-subunit-------------||-----Basic-subunit------|
        |-----------------About-480-to-500-residues-----------------|

'C': conserved cysteine involved in a disulphide bond.
Members of the 11-S family include pea and broad bean legumins, oil seed rape cruciferin, rice glutelins, cotton beta-globulins, soybean glycinins, pumpkin 11-S globulin, oat globulin, sunflower helianthinin G3, etc. This family represents the precursor protein which is cleaved into the two chains. These proteins contain two beta-barrel domains. This family is a member of the 'cupin' superfamily on the basis of their conserved barrel domain ('cupa' is the Latin term for a small barrel).

The signature pattern for this family includes the conserved cleavage site between the acidic and basic subunits (Asn-Gly) and a proximal cysteine residue which is involved in the inter-chain disulphide bond.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns