INVESTIGADORES
GONZALEZ Daniel Hector
artículos
Título:
Cell-type-specific expression of plant cytochrome c mRNA in developing flowers and roots
Autor/es:
RIBICHICH, KARINA F.; TIONI, MARIANA F.; CHAN, RAQUEL L.; GONZALEZ, DANIEL H.
Revista:
PLANT PHYSIOLOGY.
Editorial:
AMER SOC PLANT BIOLOGISTS
Referencias:
Año: 2001 vol. 125 p. 1603 - 1610
ISSN:
0032-0889
Resumen:
We have used RNA in situ hybridization to analyze the expression of
transcripts encoding cytochrome c in different tissues and organs of
sunflower (Helianthus annuus). Although northern-blot hybridization
experiments indicate that the relative abundance of transcripts does not
vary greatly, we have detected important changes in localization during
flower development. Enhanced expression is observed in floral meristems
as soon as they are discernible from the central portion of the
capitulum containing the inflorescence meristem. As flowers develop,
labeling is observed in all developing floral organ primordia. Later in
development, expression in petals is reduced, and only the central
portion of the flower becomes labeled. During the process of stamen
formation, hybridization signals were obtained mainly in anthers. Less
developed flowers at this stage showed expression through the
archesporial tissue. During meiosis, the label was observed mainly in
tapetal cells. Specific expression patterns, similar to those obtained
for sunflower, were observed when Arabidopsis flowers were analyzed with
a homologous cytochrome c probe. Specific patterns of expression were
also observed in young sunflower roots. In this case, enhanced
expression was detected in developing endodermis and pericycle and in
protoxylem initials. We conclude that cell-specific mechanisms operate
to regulate the abundance of cytochrome c encoding transcripts in
different plant tissues. The overlap between the expression patterns of
the nuclear encoded cytochrome c gene and some mitochondrial genes
suggests the existence of coordinated mechanisms of expression.