cDNA molecular cloning and seasonal accumulation of an ebulin l-related dimeric lectin of dwarf elder (Sambucus ebulus L) leaves.
SELld is a dimeric D-galactose and mucin-binding lectin (apparent Mr 68000) which coexists with the non-toxic type 2 ribosome-inactivating protein (RIP) ebulin l in dwarf elder (Sambucus ebulus L.) leaves. To ascertain a potential structural correlation with ebulin l molecular cloning of a cDNA coding for SELld was performed. SELld shared a 76% of identity with the ebulin l-B chain. Notably, it was found that SELld has Tyr present in the high affinity 2gamma sugar-binding domain of ricin which is absent in ebulin l-B chain and which seems responsible of the low cell and in vivo toxicities of ebulin l. The concentration of ebulin l in leaves decreased along the developmental stage of dwarf elder and almost disappeared in senescence while the content in SELld changed in the opposite way. Our results suggest that SELld and ebulin l play different biological roles in dwarf elder leaves.
Rojo
M Angeles
MA
Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain.
Citores
Lucía
L
Arias
F Javier
FJ
Ferreras
J Miguel
JM
Jimenez
Pilar
P
Girbés
Tomás
T
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases / Q000235:genetics / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D037121:Plant Lectins / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D054790:Ribosome Inactivating Proteins, Type 2; D012278:Ricinus / Q000235:genetics; D027923:Sambucus / Q000235:genetics / Q000378:metabolism*; D012621:Seasons; D017385:Sequence Homology
D017931:DNA Primers; D018076:DNA, Complementary; D037121:Plant Lectins; D010940:Plant Proteins; D054790:Ribosome Inactivating Proteins, Type 2; D009699:N-Glycosyl Hydrolases