Biosynthesis, cDNA and amino acid sequences of a precursor of conglutin ?, a sulphur-rich protein from Lupinus angustifolius

Abstract

The biosynthesis of conglutin delta has been studied in developing cotyledons of Lupinus angustifolius L. Precursors of conglutin delta formed the major sink for [35S]-cysteine incorporated by developing lupin cotyledons, and these precursors were rapidly sequestered into the endoplasmic reticulum. The sequence of a cDNA clone coding for one such precursor of conglutin delta was determined. The structure of the precursor polypeptide for conglutin delta predicted from the cDNA sequence contained an N-terminal leader peptide of 22 amino acids directly preceding a subunit polypeptide of Mr 4520, together with a linking region of 13 amino acids and a subunit polypeptide of Mr 9558 at the C-terminus. The amino acid sequence predicted from the cDNA sequence showed minor variations from that established by sequencing of the protein purified from mature dried seeds (Lilley and Inglis, 1986). These were consistent with the existence of a multi-gene family coding for conglutin delta. Comparison of the sequences of conglutin delta with those of other 2S storage proteins showed that the cysteines involved in internal disulphide bridges between the mature subunits of conglutin delta, were maintained throughout this family of proteins but that little else was conserved either at the protein or DNA level.

Isolation and characterization of natural Ara h 6: Evidence for a further peanut allergen with putative clinical relevance based on resistance to pepsin digestion and heat

“…This was also described for other seed storage proteins, e. g., for conglutin-d from lupine with nine cysteines in the primary sequence. The disulphide structure has been reported [29]. One cysteine is left unpaired again indicating the variant types of 2S albumins.…”

Seed storage proteins: structures and biosynthesis.

“…For example, the 2S albumins shown all contain eight cysteine residues that are conserved in terms of context and position, including Cys-Cys and Cys-Xaa-Cys motifs, which are present in many of the other proteins. Based on data of Sharief and Li (1982), Crouch et al (1983), Bartels et al (1986), Boronat et al (1986), Higgins et al (1986, Lilley and Inglis (1986), Pedersen et al (1986), Halford et al (1987), Egorov (1988), Chestnut et al (1989), Masumura et al (1989), Gayler et al (1990), Irwin et al (1990, Entwistle et al (1991), Kortt et al (1991), and . The sunflower albumin structure and the disulfide structure of SFA8 are unpublished results of A. Tatham, J. Napier, R. Fido, P. Thoyts, T. Egorov, and P. Shewry.…”

Isolation, characterization, cDNA cloning and gene expression of an avian transthyretin

“…The experimental details were as described previously [2,34] with the following exceptions : (a) the tracer RNA (approximately 720 bases) was transcribed in vitro [53] with bacteriophage SP6 RNA polymerase from a DNA template constructed by insertion of a conglutin 6 cDNA from Lupinus angustifolius [54] at the unique EcoRI restriction endonuclease site of plasmid pGEM-4Z; (b) the transthyretin antisense RNA probe used in ribonuclease protection assays was transcribed from a DNA template constructed by insertion of a chicken liver transthyretin cDNA (described in Results) at the unique EcoRI restriction endonuclease site of plasmid pGEM-3Zf(+); (c) the molecular mass of chicken transthyretin mRNA was assumed to be 240 kDa (based on the size of chicken transthyretin mRNA and the average molecular mass of ribonucleotides).…”