Molecular Plant Breeding, 2016, Vol.7, No.16, 1-7
6
it regulates the expression of its immediate target
genes like Ethylene Response Factor1 (ERF1)
(Alonso et al., 1999; Chao et al., 1997 and Solano et
al., 1998). This factor belongs to a large family of
transcription factors containing APETALA2 domain.
Transcription factors of this family GCC box, present
in ethylene inducible gene’s promoters (Hao et al.,
1998). Thus, a transcriptional cascade that is
interceded by EIN3/EIN3-like (EIL) and Ethylene
Response Factor1 escorts the ethylene controlled gene
expression regulation.
By using molecular genetics and bioinformatics tools
prime signaling components of ethylene pathway has
been identified in Arabidopsis thaliana that are
multiple membrane receptors, nuclear transcription
factor families, an intracellular signaling protein
kinase (PK), a membrane transporter-like regulator
and F-box proteins (Johnson and Ecker, 1998; Chang
et al., 1993 and Solano et al., 1998). The existence and
identifications of these key ethylene related regulators
in about all plant species has allude to highly
conserved nature of this ethylene signaling pathway
that have developed for functioning in sundry
lifestyles and developmental programs.
7 Outlook
Ethylene as a gaseous phytohormone has been
attaining great interest of plant scientists for few
decades.
Ethylene signaling,
perception and
integration of identified genetic components and
regulators into mechanistic proceedings and events at
genetic as well as molecular level are the current
challenges. For elucidating and expliciting the
ethylene functional role in signaling pathway, the
direct and specific regulatory components of ethylene
linked networks should be distinguished from indirect,
shared or general regulators as well as mediators.
Understanding of molecular interaction of ethylene
with other plant hormones is a novel aspect for plant
physiologists that unravel unique underlying
mechanisms. This would explicit ethylene related
responses that drive coordination and interaction of
endogenous developmental routes as well as internal
programs with external environmental signals or
stimuli for modulating and adapting plant’s
physiology for its survival and growth.
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