Cinammyl Alcohol DesidrogenaseTgCAD1Tectona grandis

clattergumneckΒιοτεχνολογία

23 Οκτ 2013 (πριν από 3 χρόνια και 8 μήνες)

117 εμφανίσεις

T
ree
-
rings dendroclimatological signals
,

wood expression profile

and
genomic characterization of
Cinammyl Alcohol Desidrogenase

gene
(
TgCAD1
) in Teak (
Tectona grandis

L.f.)


Esteban Galeano
*

Tarcísio Sales Vasconcelos


Mario Tomazello
-
Filho

Helaine Carrer
.


*
São Paulo University


Piracicaba, SP. 13418
-
900.
Brazil
.

egalean@usp.br




Keywords:

lignin biosynthesis, bioinformatics,
d
endroclimatology,

cross
-
dating,

central Brazil.


Teak (
Tectona grandis

Lf), tree native to tropical Southeast Asia, is currently the preferred
choice in timber trade due to wood high quality and properties, however, there are
concerns governing teak research

and market

as tree growth low rates,
issue related to
metabolic pro
cesses of wood differentiation and growth, and can be understood through
genomic studies
, tree
-
ring
and dendrochronology
analysis
.

However, there is a la
ck of
research on the genetics,
molecular

and wood

characterization of tropical forest species,
especia
lly

in

teak
, and
Cinnamyl alcohol dehydrogenase

(
CAD
) gene

plays an important
role in vascular plants wood formation
. T
he objective
s

of this research w
ere

to
study teak
wood anatomy

and

dendroclimatology potentiality,
to
characterize
CAD

gene and
expression profiles in secondary wood tissue of teak

and finally
to
relate expression with
teak wood anatomy
.
Consequently
,
d
egenerate primers of different genus were used to
identify the
TgCAD1
,
PCR products were sequenced
,
analyzed
, it was
esta
blished
amino
acid
similarities and
TgCAD1

“.pdb” file

was used for
enzyme crystal structural c
omparing,
modeling and analysis.
Real Time RT
-
PCR expression analysis was performed in leaves,
branches, stem
, hardwood,
sapwood
and core
length from 12 and 60
year old teak
plant
ations in Piracicaba, Sao Paulo,

Brazil, after performing RNA extraction and cDNA
synthesis
.
S
urface of twelve 60

teak
years old

samples were measured
and analyzed with
COFECHA

followed by
climatic data
analysis with
ARSTAN
.

As
results
,
TgCAD1

gene
translates conserved domain

showing
proximity
with
AtCAD1

and
PtCAD12
, s
tructure
m
odeling show
ed

3D

similarity to
AtCAD5
,
it

is preferentially expressed in hardwood and
branches.
Teak holds datable and climatic detectable growth rings annually,

its growth is
limited by local rainfall and temperature

and
m
aster chronology showed alternating periods
of low
-
high rainfall years, matching with known principal drought episodes in Piracicaba
.

As conclusions
,
TgCAD
1

adjusts with
AtCAD1

and
PtCAD2
, with
similar domains
,
functions
, structural and catalytic sites.
Teak wood a
natomi
cal analysis

allow

to correlate
molecular and genetic events with
anatomical
characteristics
being

possible to esteem
gene expression even in tissues with little cellular activity, as
hardwood, sapwood and
core
;
TgCAD
1

is preferentially expressed in tissues with a traction force in constant
increase
-
congruent with
Populus

results
-
, expression

temporar
y and spatially associated
with lignified tissues.
A detailed knowledge of
TgCAD
1

expression

patterns
, wood
anatomy and dendroclimatology in teak is important in biotechnology

context
,
plant
transformation
,
transcriptome and metabolome studies

and

encourages

discovery of new
genes

and
understanding of lignin deposition and cell death

genetic programming
.