Title:	A novel sugary cassava (Manihot esculenta Crantz) accumulating phyto-glycogen in the storage root may be mutated in the gene coding for the branching enzyme.
Authors:	CARVALHO, L. J. C. B. SOUZA, C. R, B, de CASCARDO, J. C. de M
Affiliation:	LUIZ JOAQUIM CASTELO B CARVALHO, CENARGEN; CLAUDIA REGINA BATISTA DE SOUZA, UNIVERSIDADE FEDERAL DO PARA; JULIO CÉSAR DE MATTOS CASCARDO, UNIVERSIDADE ESTADUAL DE SANTA CRUZ.
Date Issued:	2004
Citation:	In: IINTERNATIONAL SCIENTIFIC MEETING CASSAVA BIOTECHOLOGY NETWORK, 6., 2004, Cali. Celebrating cassava diversity: a contribution from EMBRAPA/LBB. Brasília, DF: Embrapa Recursos Genéticos e Biotecnologia, 2004. 1CD-ROM. (Embrapa Recursos Genéticos e Biotecnologia. Documentos, 111). Organized by Luiz J. C. B. Carvalho.
Description:	A new class of cassava (Manihot esculenta Crantz) storage root, named sugary cassava, has been described with accumulation of a diverse starch type (Carvalho et al. 2000; Carvalho et al. 2004). A gene expression analyses for the major enzymes in the starch pathway is showed in the present report for the clone CAS36.1 which accumulates a glycogen like starch. cDNA clones for the genes coding for sucrose synthase, plastidic phosphoglucomutase, cytosolic phosphoglucomutase, ADPG pyrophosphorilase, starch synthase, branching enzyme and debranching enzyme (isoamilase I) were used as probe in gene expression analysis of the storage root of the sugary clone (CAS36.1) and farina type (IAC12- 829) cassava. All the genes were expressed in both types of cassava except the gene coding for branching enzyme. This result strongly suggests that this gene is mutated, some how, altering the expression of the protein enzyme responsible for the formation of amylopectin in the sugary cassava CAS36.1. Sequence homology analysis of a cDNA fragment of this gene was carried out indicating that the non expressed branching enzyme gene in the storage root of the clone CAS36.1 coding to isoform I described for cassava. This gene is also not expressed in the leaf of this sugary cassava. Further research is underway in our lab to analyze the molecular genetics mechanism responsible for the differential expression of this gene.
Keywords:	Manihot esculenta Crantz
Type of Material:	Artigo em anais e proceedings
Access:	openAccess
Appears in Collections:	Artigo em anais de congresso (CENARGEN)