INVESTIGADORES
GONZALEZ Daniel Hector
artículos
Título:
Functional interconnections of Arabidopsis exon junction complex proteins and genes at multiple steps of gene expression
Autor/es:
MUFARREGE, EDUARDO F.; GONZALEZ, DANIEL H.; CURI, GRACIELA C.
Revista:
JOURNAL OF EXPERIMENTAL BOTANY
Editorial:
OXFORD UNIV PRESS
Referencias:
Lugar: Oxford; Año: 2011 vol. 62 p. 5025 - 5036
ISSN:
0022-0957
Resumen:
The exon junction complex (EJC) is
deposited on mRNA after splicing and participates in several aspects of RNA
metabolism, from intracellular transport to translation. In this work, we have
analyzed the functional and molecular interactions of Arabidopsis homologues of
Mago, Y14 and PYM, three EJC components that particpate in intron mediated
enhancement of gene expression in animals. AtMago, AtY14 and AtPYM are encoded
by single genes that show similar expression patterns and contain common
regulatory elements, known as site II, that are required for expression. AtPYM
and AtY14 are phosphorylated by plant extracts and this modification regulates
complex formation between both proteins. In addition, overexpression of AtMago
and AtY14 in plants produces an increase in AtPYM protein levels, while
overexpression of AtPYM results in increased formation of a complex that
contains the three proteins. The effect of AtMago and AtY14 on AtPYM expression
is most likely due to intron mediated enhacement of AtPYM expression, since the
AtPYM gene contains a leader intron
that is required for expression. Indeed, transient transformation asssays
indicated that the three proteins are able to increase expression from reporter
constructs that contain leader introns required for the expression of different
genes. The results indicate that the plant homologues of Mago, Y14 and PYM are
closely interconnected, not only through their function as EJC components but
also at different steps of their own gene expression mechanisms, probably
reflecting the importance of their interaction for the correct expression of
plant genes.