Ethylene Perception and Signalling in Ripening Fruit - Fruit Ripening: Physiology, Signalling and Genomics - page 207

11.5 Conclusions and Prospects

identifi cation of fruit ripening-specifi c small
RNAs, including microRNAs and small
interfering RNAs, will help in further
elucidation of the post-transcriptional
regulation of expression of ethylene-related
ripening-specifi c genes (Zuo et al. , 2012).
The recently completed tomato genome
sequencing project will also help in fi nding
the chromosomal locations of ripening-
specifi c genes, and will result in identifi -
cation of various common regulatory
sequences present in the promoters of
ripening-related genes that will ultimately
help in unravelling the regulatory mech-
anism of their spatial/temporal expression.
The availability of such genomic resources
for other fruit species will promote
opportunities to understand various aspects
of fruit development and ripening and to
apply this knowledge for crop improvement.

The initiation and subsequent coordinated
manifestation of ripening events is a highly
complex phenomenon that depends on
several internal factors, including the type
and category of fruit, developmental regu-
lation and complex interactive hormonal
networks, as well as numerous external
factors including light, temperature, and
biotic and abiotic stress. Ethylene is one of
the main determinants of ripening in
climacteric fruits. As most of the ethylene
signalling components, upstream of the ERF
proteins and above the levels of ERFs, have
already been characterized during ripening,
the current emphasis is on characterizing
additional ripening-related ERFs in tomato.
Characterization of these transcription
factors and their interactions with targets is
likely to result in a better understanding of
the molecular mechanisms of ethylene
signalling, underlying ripening in fl eshy
fruits. Several genomics tools such as
microarray resources have already been
utilized to gain an insight into the ethylene-
dependent aspects of ripening in tomato
(Alba et al. , 2005; Osorio et al. , 2011;
Kumar et al. , 2012b). Furthermore, the

Acknowledgements

The authors thank the Department of
Biotechnology, Government of India, for
fi nancial support. R.K. acknowledges CSIR,
India, for the fellowship granted during his
tenure as a research fellow.

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