Brassinolides and IAA induce the transcription of four alpha-expansin genes related to development in Cicer arietinum.
Four different cDNAs encoding alpha-expansins have been identified in Cicer arietinum (Ca-EXPA1, Ca-EXPA2, Ca-EXPA3 and Ca-EXPA4). The shared amino acid sequence similarity among the four alpha-expansin proteins ranged from 67 to 89%. All of them display common characteristics such as molecular mass (around 24 kDa), amino acid numbers, and also the presence of a signal peptide. The transcription pattern of chickpea alpha-expansin genes in seedlings and plants suggests a specific role for each of the four alpha-expansins in different phases of development or in different plant organs. High levels of Ca-EXPA2 transcripts coincide with maximum epicotyl and stem growth, indicating an important involvement of this particular alpha-expansin in elongating tissues. Ca-EXPA3 would be related to radicle development, while Ca-EXPA4 seems to be involved in pod development. A considerable increase in the level of all Ca-EXPA transcripts accompanied the indole acetic acid (IAA) plus brassinolide (BR)-induced elongation of excised epicotyl segments. This IAA + BR induction was seen even for the chickpea expansin genes whose transcription was not affected by IAA or BR alone.
Departamento de Fisiología Vegetal, Facultad de Biología, Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Pza Doctores de la Reina s/n, Salamanca 37007, Spain.
Ma Angeles
MA
Sánchez
Isabel
I
Mateos
Emilia
E
Labrador
Berta
B
Dopico
D000595:Amino Acid Sequence; D060406:Brassinosteroids; D002777:Cholestanols / Q000494:pharmacology*; D029863:Cicer / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D015723:Gene Library; D007210:Indoleacetic Acids / Q000494:pharmacology*; D008969:Molecular Sequence Data; D005810:Multigene Family; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics*; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D036226:Seedlings / Q000235:genetics / Q000254:growth & development; D013260:Steroids, Heterocyclic / Q000494:pharmacology*; D014158:Transcription, Genetic / Q000187:drug effects / Q000235:genetics
D060406:Brassinosteroids; D002777:Cholestanols; D018076:DNA, Complementary; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins; D012337:RNA, Ribosomal, 18S; D013260:Steroids, Heterocyclic; C095825:expansin protein, plant; C030737:indoleacetic acid; C023623:brassinolide