Disulphide Bonding in a Stylar Self‐Incompatibility Ribonuclease of Nicotiana Alata
- 1 November 1996
- journal article
- Published by Wiley in European Journal of Biochemistry
- Vol. 242 (1) , 75-80
- https://doi.org/10.1111/j.1432-1033.1996.0075r.x
Abstract
Many flowering plants have developed a self‐incompatibility mechanism, which is controlled by a single polyallelic locus (the S‐locus), to prevent inbreeding. The products of the S‐locus in the styles of solanaceous plants are an allelic series of glycoproteins with RNase activity [McClure, B. A., Haring, V., Ebert, P. R., Anderson, M. A., Simpson, R. J., Sakiyama, F. & Clarke, A. E. (1989) Nature 342, 955–957]. These S‐RNases show some amino‐acid‐sequence similarity with two fungal RNases (T2 and Rh), including the presence of two active‐site His residues, which suggests a common three‐dimensional structure. Disulphide bonding is important in the maintenance of the three‐dimensional structure of the fungal RNases [Kurihara, H., Mitsui, Y., Ohgi, K., Irie, M., Mizuno, H. & Nakamura, T. (1992) FEBS Lett. 306, 189–192] and the S‐RNases [Tsai, D. S., Lee, H.‐S., Post, L. C., Kreiling, K. M. & Kao, T.‐H. (1992) Sex. Plant Reprod. 5, 256–263]. We have used the S2‐allele RNase of Nicotiana alata, which has nine Cys residues, to establish the pattern of disulphide bonding. The disulphide bonds Cys16–Cys21, Cys45–Cys94, Cys153–Cys182 and Cys165–Cys176 are consistent with the S2‐RNase having a similar three‐dimensional structure to RNase Rh. A free Cys residue (Cys95) adjacent to Cys45‐Cys94 promotes a rapid specific disulphide migration when the protein is exposed to denaturing conditions.Keywords
This publication has 21 references indexed in Scilit:
- Structure of N-glycans on the S3- and S6-stylar self-incompatibility ribonucleases of Nicotiana alataGlycobiology, 1996
- Cloning and Nucleotide Sequence of the S7-RNase from Nicotiana alata Link and OttoPlant Physiology, 1995
- MOLECULAR ASPECTS OF SELF-INCOMPATIBILITY IN FLOWERING PLANTSAnnual Review of Genetics, 1993
- Molecular Aspects of Self-Incompatibility in Flowering PlantsAnnual Review of Genetics, 1993
- Crystal and molecular structure of RNase Rh, a new class of microbial ribonuclease from Rhizopus niveusFEBS Letters, 1992
- Structural analysis of the N-linked glycan chains from a stylar glycoprotein associated with expression of self-incompatibility in Nicotiana alataGlycobiology, 1992
- Self-incompatibility in Nicotiana alata involves degradation of pollen rRNANature, 1990
- Identification, isolation, and N-terminal sequencing of style glycoproteins associated with self-incompatibility in Nicotiana alata.Plant Cell, 1989
- Sequence variability of three alleles of the self-incompatibility gene of Nicotiana alata.Plant Cell, 1989
- Cloning of cDNA for a stylar glycoprotein associated with expression of self-incompatibility in Nicotiana alataNature, 1986