Plant Molecular Biology 36: 885–895, 1998.
1998 Kluwer Academic Publishers. Printed in Belgium.
Molecular cloning of a novel heat induced/chilling tolerance related cDNA
in tomato fruit by use of mRNA differential display
Dina K. Kadyrzhanova, Konstantinos E. Vlachonasios, Philippos Ververidis
David R. Dilley
Department of Horticulture, Plant and Soil Sciences Building, Michigan State University, East Lansing,
MI 48824, USA;
(current address: Institute of Molecular Biology and Biotechnology, Foundation for Research
and Technology, P.O. Box 1527, Heraklion 711 10, Crete, Hellas, Greece;
author for correspondence)
Received 19 February 1997; accepted in revised form 25 November 1997
Key words: chilling injury, heat shock protein, tomato
Chilling injury was circumvented by heat-treating mature green tomatoes (Lycopersicon esculentum, cv. Mountain
Springs) at 42
C for two days prior to storing them at 2
C for one or two weeks, whereas fruits stored at 2
display and screening of the cDNA libraries, we have cloned from tomato fruit a full-length HCT1 cDNA (heat
induced/chilling tolerance related). The protein (17.6 kDa) predicted from coding region of HCT1 cDNA has high
identity with class II cytosolic small HSPs. The gene corresponding to HCT1 cDNA was termed as LeHSP 17.6.
Southern-blothybridizationindicatesthat LeHSP17.6belongsto a two-membergenefamily. Northernblot analysis
to chilling temperatures for at least one week and upon transfer to ripening temperatures for one day. Fruits which
were only chilled show a low level of expression of the LeHSP 17.6 transcript. We hypothesize that LeHSP 17.6
may be involved in protecting the cell from metabolic dysfunctions leading to ripening failure caused by chilling
injury. This is the ﬁrst report of a class II cytosolic smHSPs encoding gene in tomato.
The useful postharvest life of many fruits of tropical
or subtropical origin is limited because they must be
stored above 10–12
C to avoid chilling injury .
For example, if mature green tomatoes are stored for
only a few days at temperatures below 10
C and sub-
sequently returned to a normally permissive ripening
temperature, they fail to ripen and become susceptible
to microbial spoilage . Prestorage heat-treatment
has been found to increase the chilling tolerance of
tomato and other subtropical fruits [17, 36, 38, 56].
GenBank Accession No. of the LeHSP 17.6 cDNA sequence
This research was partially funded by the United States–Israel
Binational Agricultural Research and Development Fund (BARD
No. 15–2175–92R) and the Michigan Agricultural Experiment
Increased tolerance to chilling injury by high temper-
ature treatment has been related to the accumulation
of heat shock proteins (HSPs) [27, 36]. Plant HSPs
consist of a few high molecular weight classes 60 kD,
70 kD, 90 kD, 100 kD and a complex group of low
molecular weight proteins with molecular sizes ran-
17 to 30 kD [23, 43, 65]. The small HSPs
are structurally related and are encoded by six discrete
gene families . Classes I and II encode cytosolic
proteins while classes III and IV encode chloroplast
and endoplasmic reticulum localized proteins[16, 65].
For class VI, which is represented by a single 22.3 kD
HSP from soybean, the intracellular location is pro-
posed to be the endoplasmic reticulum . Cytosolic
small HSPs are particularly abundant in plants subjec-
ted to stress conditions but their speciﬁc functions are
notknown.Recently,in vitro studiesdemonstratedthat