eprintid: 5902 rev_number: 17 eprint_status: archive userid: 1903 dir: disk0/00/00/59/02 datestamp: 2011-02-07 09:25:46 lastmod: 2016-04-20 14:35:45 status_changed: 2011-02-07 09:25:46 type: article metadata_visibility: show item_issues_count: 0 creators_name: Ponz Ascaso, Fernando creators_name: Paz Ares, Javier creators_name: Hernandez Lucas, Carlos creators_name: García Olmedo, Francisco creators_name: Carbonero Zalduegui, Pilar title: Cloning and nucleotide sequence of a cDNA encoding the precursor of the barley toxin a-hordothionin ispublished: pub subjects: biologia abstract: 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 date: 1986-04 date_type: published publisher: Wiley-Blackwell official_url: http://onlinelibrary.wiley.com/doi/10.1111/j.1432-1033.1986.tb09557.x/abstract id_number: 10.1111/j.1432-1033.1986.tb09557.x full_text_status: public publication: European Journal of Biochemistry volume: 156 number: 1 pagerange: 131-135 institution: Agronomos department: Biotecnologia refereed: TRUE issn: 1432-1033 rights: by-nc-nd citation: Ponz Ascaso, Fernando and Paz Ares, Javier and Hernandez Lucas, Carlos and García Olmedo, Francisco and Carbonero Zalduegui, Pilar (1986). Cloning and nucleotide sequence of a cDNA encoding the precursor of the barley toxin a-hordothionin. "European Journal of Biochemistry", v. 156 (n. 1); pp. 131-135. ISSN 1432-1033. https://doi.org/10.1111/j.1432-1033.1986.tb09557.x . document_url: https://oa.upm.es/5902/1/olmedo_078.pdf