Proceedings of the XLV Italian Society of Agricultural Genetics - SIGA Annual Congress

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

Poster Abstract

RELATIONSHIPS BETWEEN CULTIVATED AND WILD LENS SPECIES BASED ON LECTIN GENE SEQUENCE

GALASSO I.*, SPARVOLI F.**, LANAVE C.***, LIOI L.*, BOLLINI R.**

* Istituto del Germoplasma, CNR, Bari

germtg13@area.ba.cnr.it, germll08@area.ba.cnr.it

** Istituto Biosintesi Vegetali, CNR, Milano

sparvoli@ibv.mi.cnr.it, bollini@ibv.mi.cnr.it

*** Centro di Studio Mitocondri e Metabolismo Energetico, CNR, Bari

cecilia@area.ba.cnr.it

lectin gene, seed storage protein, Lens ssp.

The genus Lens Miller comprises six annual species of which only Lens culinaris subsp. culinaris is cultivated. Knowledge of the taxonomic relationships among crops and their wild relatives is required when alien germplasm is used in breeding programmes in order to widen the genetic base of the cultivated species.

Lectins are proteins with sugar binding properties and have been found in different amounts in most plant tissues. In Phaseolus seeds, lectin and lectin-like proteins are coded by multigene families and their nucleotide sequences have been successfully used for evolutionary and phylogenetic studies.

In this study, we have investigated the possibility to isolate lectin gene(s) present in the genome of cultivated and wild Lens species. Although the amino acid sequence of a mature lectin protein from lentil has been published, no molecular data are available for its coding gene. Since Pisum sativum belongs to the same tribe as Lens, primers for PCR amplification have been designed based on conserved regions of the lectin nucleotide sequence of P. sativum. Sequencing of the PCR products showed that only one type of lectin is present in each Lens taxon, and that a high degree of similarity exists among the lectin genes of the different Lens species. A FASTA search of these sequences in the EMBL nucleotide database confirmed that lectin genes from Lens share a high similarity with the nucleotide sequences of pea lectin and, to a lesser extent, with the lectin genes of other legume species belonging to the Vicieae tribe. Evolutionary distances among the lectin sequences from wild and cultivated Lens taxa were used to construct a rooted phylogenetic tree. Apart from L. nigricans that shows the greatest distance from the other taxa analysed, two main clusters could be distinguished: one containing L. tomentosus, the cultivated species L. culinaris subsp. culinaris and its wild progenitor L. culinaris subsp. orientalis, while the other one encloses the wild species L. lamottei, L. odemensis and L. ervoides.

Research partially supported by MURST - CLUSTER C03 Ingegneria Genetica “Studio di geni d’interesse biomedico ed agroalimentare”