Domain

CND41-like (IPR033873)

Short name: CND41-like

Overlapping homologous superfamilies

Domain relationships

Description

This entry represents the aspartic peptidase domain found in CND41-like proteins. Chloroplast Nucleoids DNA-binding Protease catalyzes the degradation of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) in senescent leaves of tobacco. Antisense tobacco with reduced amount of CND41 maintained green leaves and constant protein levels, especially Rubisco. CND41 has DNA-binding as well as aspartic protease activities. The aspartic protease domain is located at the C terminus of the protein [PMID: 15252735,PMID: 16021504].

There are five paralogues in Arabidopsis thaliana, the products of the genes At1g01300, At1g79720, At3g20015, At3g61820 and At5g10770. All are included in this entry.

Aspartyl proteases (APs), also known as acid proteases, (EC:3.4.23.-) are a widely distributed family of proteolytic enzymes [PMID: 6795036, PMID: 2194475, PMID: 1851433, PMID: 15771507, PMID: 24869856, PMID: 1455179] known to exist in vertebrates, fungi, plants, retroviruses and some plant viruses. APs use an Asp dyad to hydrolyze peptide bonds.

APs found in eukaryotic cells are alpha/beta monomers composed of two asymmetric lobes ("bilobed"). Each of the lobes provides a catalytic Asp residue, positioned within the hallmark motif Asp-Thr/Ser-Gly, to the active site. The N- and C-terminal domains, although structurally related by a 2-fold axis, have only limited sequence homology except the vicinity of the active site. This suggests that the enzymes evolved by an ancient duplication event. The enzymes specifically cleave bonds in peptides which have at least six residues in length with hydrophobic residues in both the P1 and P1' positions. The active site is located at the groove formed by the two lobes, with an extended loop projecting over the cleft to form an 11-residue flap, which encloses substrates and inhibitors in the active site. Specificity is determined by nearest-neighbour hydrophobic residues surrounding the catalytic aspartates, and by three residues in the flap. The enzymes are mostly secreted from cells as inactive proenzymes that activate autocatalytically at acidic pH. Eukaryotic APs form peptidase family A1 of clan AA.

Contributing signatures

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