The complete amino acid sequence of ribonuclease from the seeds of bitter gourd (Momordica charantia)

Abstract

The complete amino acid sequence of ribonuclease (RNase MC) from the seeds of bitter gourd (Motttordica ch=anria) has been determined, This has been achieved by the sequence analysis of peptides derived by enzymatic digestion with trypsin. lysylendopeptidase. and chymotrypsin, as well as by chemical cleavage with cyanogen bromide. The protein contains 191 amino acid residues and has a calculated molecular mass of 21259 Da.Comparison of this sequence with sequences of the fungal RNases. RNase T2, and RNase Rh, revealed that there are highly conserved residues at positions 32-38 (TXHGLWP) and 81-92 (FWXHEWXKHGTC).Furthermore. the sequence of RNase MC was found to be homologous to those of Nicotiatta alutn S-glycoproleins involved in self-incompatibility sharing 41% identical residues.

The S-Ribonuclease Gene of Petunia hybrida Is Expressed in Nonstylar Tissue, Including Immature Anthers

“…Taylor et al (1993) have shown that mRNAs with homology to P. hybrida and N. alata S-RNases are expressed in flowers of Arabidopsis thaliana. Other related RNase sequences are found in tomato (Jost et al, 1991), Momordica charantia (Ide et al, 1991), and fungi (Horiuchi et al, 1988;Kawata et al, 1988). The S-RNases seem clearly to be related to a larger family of RNase proteins that have various roles in different plants and plant tissues.…”

“…All of the style-expressed gametophytic S-alleles that have been cloned to date show homology to a class of fungal RNases (Horiuchi et al, 1988;Kawata et al, 1988;McClure et al, 1989;Clark et al, 1990;Ioerger et al, 1991) as well as to related RNases from self-compatible species (Ide et al, 1991;Jost et al, 1991;Taylor et al, 1993). Furthermore, the S-locus proteins have RNase activity in vitro Gray et al, 1991;Singh et al, 1991) and have been renamed S-RNases to reflect this function.…”

Amino Acid Sequence and Characterization of a Rice Bran Ribonuclease

“…3) The latter enzymes are known to be induced by phosphate deprivation [Jost et al,4) Bariola et al 5) ], in the case of senescence [Lers et al 6) ], and exist in the seeds probably for defense [Ide et al, 7) Rojo et al 8,9) ]. In terms of the evolutional change of plant RNases, knowledge is limited to those plants belonging to Dicotyledoneae, except for barley.…”

“…In terms of the evolutional change of plant RNases, knowledge is limited to those plants belonging to Dicotyledoneae, except for barley. 10) These include several plants of Solanaceae [tomato, 4,11) and tobacco, 3,12) petunia 13) and a kind of potato 14) ], Cucurbitaceae [bitter gourd, 7) cucumber, 8) melon 9) ], Rosacease [pear 15) ], Arabidopsis, 16) Zinnia elegance, 17) Panax ginnseng 18) and others. In this report, we will describe the amino acid sequence of an RNase from rice bran (Oryza sativa) which is a member of Monocotyledoneae, and its enzymatic properties.…”

Base Specificity of Two Plant Seed Ribonucleases fromMomoridica charantiaandLuffa cylindrica

“…They were RNase MCI from Momoridica charantia 10 ) and RNase LCI from Luffa cylindrica. 1 0) Their primary structures were very similar to those of tomato extracellular RNase and N. alata RNase.…”