Identification, classification and expression pattern analysis of sugarcane cysteine proteinases

Abstract

Cysteine proteases are peptidyl hydrolyses dependent on a cysteine residue at the active center. The physical and chemical properties of cysteine proteases have been extensively characterized, but their precise biological functions have not yet been completely understood, although it is known that they are involved in a number of events such as protein turnover, cancer, germination, programmed cell death and senescence. Protein sequences from different cysteine proteinases, classified as members of the E.C.3.4.22 sub-sub-class, were used to perform a T-BLAST-n search on the Brazilian Sugarcane Expressed Sequence Tags project (SUCEST) data bank. Sequence homology was found with 76 cluster sequences that corresponded to possible cysteine proteinases. The alignments of these SUCEST clusters with the sequence of cysteine proteinases of known origins provided important information about the classification and possible function of these sugarcane enzymes. Inferences about the expression pattern of each gene were made by direct correlation with the SUCEST cDNA libraries from which each cluster was derived. Since no previous reports of sugarcane cysteine proteinases genes exists, this study represents a first step in the study of new biochemical, physiological and biotechnological aspects of sugarcane cysteine proteases.

Calpain chronicle—an enzyme family under multidisciplinary characterization

“…A plant calpain, now called phytocalpain, was first identified in the sugarcane EST database by Correa et al , and was named SC cal1. 262 ) A sequence similarity search using SC cal1 as bait subsequently identified other phytocalpains: from the dicotyledons, Vitis vinifera (pinot noir grape), A. thaliana , and Solanum melongena (eggplant); from the monocotyledons, Zea mays (maize), Oryza sativa (rice plant), and Hordeum vulgare (barley); and from gymnospermae, Pinus taeda (loblolly pine). 163 ) A genetic study identified phytocalpain as the defective kernel 1 ( dek1 ) gene product, DEK1, required for aleurone cell development in the maize endosperm.…”

Molecular Dynamics Simulations of the Catalytic Pathway of a Cysteine Protease: A Combined QM/MM Study of Human Cathepsin K

“…Cysteine proteases are proteolytic enzymes that catalyze the cleavage of peptide bonds by using a cysteine residue in the active site. These enzymes have been identified from diverse organisms, such as bacteria, plants, and animals, − which have been classified into nearly 50 protein families belonging to seven major clans based on the nature and sequence of the catalytic residues. , Because of the important role of these enzymes in pathological cellular processes, the reaction mechanism of cysteine proteases has been extensively investigated experimentally and computationally. One member of the papain family of cysteine proteases is human cathepsin K, which is highly expressed in osteoclasts and implicated in bone resorption. − Deficiency of cathepsin K causes the bone-sclerosing disorder pycnodysostosis, which at the molecular level is a result of insufficient degradation of type I collagen during bone remodeling, leading to osteoporosis and increased bone fragility …”

Defense-related proteins involved in sugarcane responses to biotic stress

“…Endoproteinase genes with diverse substrate specificity are reported in sugarcane, but their involvement in plant defense remains to be explored ( Correa et al , 2001 ; Ramos and Selistre-de-Araujo, 2001 ; Santos-Silva et al ., 2012 ).…”