title: Cloning and nucleotide sequence of a cDNA encoding the precursor of the barley toxin a-hordothionin
creator: Ponz Ascaso, Fernando
creator: Paz Ares, Javier
creator: Hernandez Lucas, Carlos
creator: García Olmedo, Francisco
creator: Carbonero Zalduegui, Pilar
subject: Biology
description: A cDNA library, prepared from developing barley endosperm, was screened for thionin recombinants. Clone pTH1 was that with the largest insert out of three identified. The longest reading frame in the 610-base-pair insert codes for a protein of 127 amino acids that includes an internal sequence of 45 amino acids, which is identical to that obtained for the α-hordothionin by direct protein sequencing. The deduced thionin sequence is preceded by a leader sequence of 18 residues and followed by a sequence that corresponds to an acidic protein of 64 amino acids. This structure supports previous evidence indicating that thionin is synthesized as a much larger precursor, which undergoes two processing steps: the cotranslational cleavage of a leader sequence and the post-translational one of a larger peptide. The size of the mRNA was estimated to be about 950 bases by Northern analysis. Thionin concentration in mature endosperm of barley cv. Bomi was about twice that of its high-lysine mutant Risç 1508. The same difference was observed in thionin mRNA in the corresponding developing endosperms, indicating that gene expression is partially blocked in the mutant at a pretranslational level
publisher: E.T.S.I. Agrónomos (UPM)
rights: https://creativecommons.org/licenses/by-nc-nd/3.0/es/
date: 1986-04
type: info:eu-repo/semantics/article
type: Article
source: European Journal of Biochemistry, ISSN 1432-1033, 1986-04, Vol. 156, No. 1
type: PeerReviewed
format: application/pdf
language: eng
relation: http://onlinelibrary.wiley.com/doi/10.1111/j.1432-1033.1986.tb09557.x/abstract
rights: info:eu-repo/semantics/openAccess
relation: info:eu-repo/semantics/altIdentifier/doi/10.1111/j.1432-1033.1986.tb09557.x
identifier: https://oa.upm.es/5902/