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29 $page->header('The Seymour Lab', undef, $stylesheet);
33 <h1
>The Seymour Lab
</h1
>
36 <p
class="footnote" style
="text-align:center"><img src
=
37 "/static_content/community/feature/200409-1.jpg" border
="0" width
="570" height
="300" alt
=
38 "The Seymour Lab" /><br />
39 Kavita Kulkarni
, Mervin Poole
, Ken Manning
, Graham B
. Seymour
,
40 Alex Popovich
and Peter G
. Walley
</p
>
42 <p
>Fleshy fruits are economically highly valuable
and provide a
43 substantial part of the daily intake of vitamins
and minerals
44 whether they are consumed
in a fresh
or processed condition
.
45 There is evidence emerging that the genes that regulate ripening
46 in fruits have been conserved during evolution
. In
our laboratory
47 the aim is to isolate key members of this
class of regulatory
48 genes
and investigate their role
in ripening
. There are three
49 strands to
our work
in this area
:</p
>
51 <p
>One approach is to clone the wild type allele of the gene
52 responsible
for the Colourless non
-ripening
(Cnr
) mutation of
53 tomato
. In tomato a small number of single gene mutations exist
,
54 such as rin
, nor
and Cnr which have pleiotropic effects resulting
55 in the reduction
or almost complete abolition of ripening
. These
56 probably represent lesions
in ripening
-regulatory genes
. For
57 instance Cnr results
in a non
-ripening phenotype with two
58 distinct characteristics
: (1) firm fruit with reduced
59 cell
-to
-cell adhesion
and (2) complete abolition of carotenoid
60 biosynthesis
in the pericarp
(see Thompson et al
. Plant
61 Physiology
120: 383-389, 1999: Orfila et al
. Plant Physiology
,
62 126: 210-221, 2001). We have used a genetic
map-based approach to
63 isolate a candidate
for the gene at the Cnr locus
(T
ö
;r et
64 al
, 104: 165-170; 2002; Manning et al
, manuscript
in preparation
)
65 and want to understand its role
in juiciness
and colour
68 <p
>In collaboration with Jim Giovannoni at Cornell we are
69 investigating whether strawberry orthologues of the tomato genes
70 RIN
and NOR can modulate ripening
in this non
-climacteric fruit
.
71 Mutant alleles of these genes have previously been used
in
72 conventional breeding to enhance texture
and shelf
- life
in
73 commercial tomato
.</p
>
75 <p
>We are utilizing information from an advanced genetic
76 framework
in the dry fruited Arabidopsis to unravel the control
77 of cell separation
and softening
in fleshy fruits
. One of the
78 tomato genes
, TDR4
, is a likely orthologue of the Arabidopsis
79 gene FRUITFULL
. In Arabidopsis this MADS
-box gene is involved
in
80 the control of valve cell differentiation
(the cells
81 corresponding to the tomato pericarp
). In ful mutants
, valve
82 cells adopt the fate of dehiscence zone cells
, which are normally
83 programmed to undergo cell separation
when the fruit matures
.
84 (Ferr
á
;ndiz
, Liljegren
and Yanofsky
, 2000. Science
289,
85 436-438). We are testing whether TDR4 can substitute
for
86 FRUITFULL
in Arabidopsis
and investigating its role
in tomato
89 <p
>Other projects on
-going
in the lab include the identification
90 and resolution of QTL
for mechanical properties
in tomato fruits
91 and isolation of novel mutants affecting fruit quality
.</p
>
93 <p
>Additionally GBS is spearheading
, in collaboration with Gerard
94 Bishop at Imperial College
and Glenn Bryan at Scottish Crop
95 Research Institute
, the UK Solanaceae Research Community
96 contribution to the International effort to sequence the tomato
99 <p
class="footnote"><img src
="/static_content/community/feature/200409-2.jpg" border
="0" width
=
100 "645" height
="445" alt
="Fleshy fruits" /><br />
101 <b
>Redrawn
and modified from The Evolution of Plants
and Flowers
,
102 B
. Thomas
, Eurobook Ltd
, Wallingford
, UK
</b></p>
104 <p
>Fleshy fruits are likely to have evolved from dry forms
. Have
105 genes controlling cell separation
in ripening fruits been
106 conserved during evolution
.</p
>
108 <p
class="footnote"><img src
="/static_content/community/feature/200409-3.jpg" border
="0" width
=
109 "698" height
="562" alt
="Colourless non-ripening" /><br />
110 <b
>Colourless non
-ripening
(Cnr
)</b></p>
112 <p
>Cnr fruits show a non
-ripening phenotype with significant loss
113 of cell adhesion
in the pericarp
</p
>
115 <h2
>Contact Information
</h2
>
117 <p
>Dr Graham B
. Seymour
<br
/>
119 University of Warwick
, Wellesbourne
, Warwick CV35
9EF
, UK
.<br
/>
120 Tel
: 44 24 7657 4455<br
/>
121 Fax
24 7657 4500<br
/>
123 "mailto:graham.seymour\@warwick.ac.uk">graham
.seymour\
@warwick.ac
.uk
</a></p>
125 <h2
>Selected Recent Publications
</h2
>
127 <p
class="bibliography">Eriksson
, E
.M
., Bovy
, A
., Manning
, K
.,
128 Harrison
, L
., Andrews
, J
., De Silva
, J
., Tucker
, G
.A
. and
129 Seymour
, G
.B
. (2004). Effects of the Colourless non
-ripening
130 (Cnr
) mutation on gene expression
and cell wall biochemistry
131 during tomato fruit development
and ripening
. Plant Physiology
132 (submitted
for publication
).</p
>
134 <p
class="bibliography">Marin
, C
., Smith
, D
., Manning
, K
.,
135 Orchard
, J
. and Seymour
, G
.B
. (2003). Pectate lyase gene
136 expression
and enzyme activity
in ripening banana fruit
. Plant
137 Molecular Biology
51, 851-857.</p
>
139 <p
class="bibliography">Tor
, M
., Manning
, K
., King
, G
.J
.,
140 Thompson
, A
.J
., Jones
, G
.H
., Seymour
, G
.B
. and Armstrong
, S
. J
.
141 (2002). Genetic analysis
and FISH mapping of the Colourless
142 non
-ripening locus of tomato
. Theoretical
and Applied Genetics
145 <p
class="bibliography">Fraser
, P
.D
., Bramley
, P
. and Seymour
,
146 G
.B
. (2001). Effect of the Cnr mutation on carotenoid formation
147 during tomato fruit ripening
. Phytochemistry
58, 75-79.</p
>
149 <p
class="bibliography">King
, G
.J
., Lynn
, J
.R
., Dover
, C
.J
.,
150 Evans
, K
.M
. and Seymour
, G
.B
. (2001). Resolution of quantitative
151 trait loci
for mechanical measures accounting
for genetic
152 variation
in fruit texture of apple
(Malus pumila Mill
).
153 Theoretical
and Applied Genetics
102, 1227-1235.</p
>
155 <p
class="bibliography">Orfila
, C
., Seymour
, G
.B
., Willats
,
156 W
.G
.T
., Huxham
, I
.M
., Jarvis
, M
.C
., Dover
, C
.J
., Thompson
, A
.J
.
157 and Knox
, J
.P
. (2001). Altered middle lamella homogalacturonan
158 and disrupted deposition of
(1-5)-(-L
- arabinan
in the pericarp
159 of Cnr
, a ripening mutant of tomato
. Plant Physiology
126,
162 <p
class="bibliography">Drury
, R
., Hortensteiner
, S
., Donnison
,
163 I
., Bird
, C
.R
. and Seymour
, G
.B
. (1999). Gene expression
and
164 chlorophyll catabolism
in the peel of ripening banana fruits
.
165 Physiologia Plantarum
107, 32-38.</p
>
167 <p
class="bibliography">Huxham
, I
.M
., Jarvis
, M
.C
., Shakespeare
,
168 L
., Dover
, C
.J
., Juhnson
,D
., Knox
, J
.P
. and Seymour
, G
.B
. (1999).
169 Electron energy loss spectroscopic imaging of calcium
and
170 nitrogen
in the cell walls of apple fruits
. Planta
208,
173 <p
class="bibliography">Thompson
, A
.J
., Tor
, M
., Barry
, C
.S
.,
174 Vrebalov
, J
., Orfila
, C
., Jarvis
, M
.C
., GiovannoniI
, J
.J
.,
175 Grierson
, D
. and Seymour
, G
.B
. (1999). Molecular
and genetic
176 characterisation of a novel pleiotropic tomato ripening mutant
.
177 Plant Physiology
120, 383-389.</p
>