Triticeae Genomics and Genetics 2016, Vol.7, No.02, 1
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oxidative stress. Accordingly, protein concentrations
showed different results with increasing of salinity
level which depended on plant species and genotypes
(Rahdari
et al
. 2012). Shaddad
et al
., (2012) suggest a
greater participation of soluble sugars and proteins
than free amino acids in maintaining water relations in
both roots and shoots.
The results in table 3 and figure 1 revealed that 23
protein bands were detected in cv. Sakha 94, 18
protein bands in cv. Gimiza 11, 16 protein bands in cv.
Gimiza 10 and 18 protein bands in cv. Giza 168. The
four cultivars possessed 17 common cprotein bands
while they different from each other in 6 protein
bands.
Studying the pattern of protein synthesis under salt
stress may help to identify a protein (s) associated
with stress. In the present study, salinity induced the
synthesis of newly proteins and simultaneously
reduced other protein sets. The results revealed that
three bands at molecular weight 52.1 kDa is induced
under salinity stress in four tested cultivars Sakha 94,
Gimiza 11, Gimiza10 and Giza 168, as compared to
the control treatment. It was induced at 50 mM, 150
mM in both cultivars Gimiza 11, Gimiza 10 and Giza
168 while, induced at 50 mM, 150 mM and 300
mMNaCl levels in cv. Sakha 94 as compared to
control treatment. These results revealed that the 52.1
kDa protein band was commonly induced as a result
of salinity treatment in the four cultivars. Another
important point is the induction of protein band with
molecular weight 14.8 in cv. Sakha 94 at 50 mM and
150 mm NaCl levels but it disappeared at 300
mMNaCl. This band was absent in the cultivars
Gimiza11, Gimiza 10 and Giza 168. This result
suggested that this band was specific and responsible
for halotolerant characteristic features of cv. Sakha 94
and supports the growth parameter (crop yield),
metabolic constituents and minerals. Tammam (2003)
found that salt treatment of broad bean seedling
resulted in the disappearance of five polypeptides,
while the peptides with molecular mass 26, 18, 14and
12kDa increased in their intensity and two peptides 99
and 102 kDa appeared on the gel. Amini and
Ehsnapour (2005) stated that accumulation of proteins
in plant grown under saline condition may provide a
storage form of nitrogen that is re-utilized when stress
is over and might be due to osmotin like protein in a
particular synthesis of those proteins which are
involved in modification of cell wall. Witzel et al.,
(2014) study the root proteome was analyzed based on
two-dimensional gel electrophoresis. A number of
cultivar-specific and salinity stress-responsive proteins
were
identified.
Mass
spectrometry-based
identification was successful for 74 proteins, and a
hierarchical clustering analysis grouped these into five
clusters based on similarity of expression profile.
It is worthy to mention that salinity stress exerted
multiple effects on the production of free Amino acids
among the four wheat cultivars and their plant organs.
The correlation between proteins and amino acids in
the four wheat cultivars and their plant organs was
interestingly because:
While the total protein remained more or less
unchanged in cv. Sakha 94, amino acids enhanced
markedly in (stems, leaves, and spikes) and remained
unchanged in roots. Thus the two processes was not
interdependent, the high accumulation of amino acids
in this state is not incorporated into proteins because it
was equilibrated, there is no need to this elevation in
amino acids for protein content (a sufficient amount of
protein was synthesized in this cultivar), the high
accumulations of amino acids in this state could
directed into biological functions rather than protein
synthesis they used functionally rather than
structurally. They used as:
a-Osmoregulation to increase the internal osmotic
potential (osmotic adjustment). (Dubey and Rani,
1989; Seki et al., 2007) stated that the major
osmoregulator substance such accumulation of amino
acids in salt-stressed plants equalizes the osmotic
potential of the cytoplasm, thus maintaining the
cellular function and structure.
b-Non-enzymatic free radical scavenging components
kept the cell membranes mainly around absolute
control. The function of the accumulation of amino
acids is often associated with osmotic adjustment by
lowering the water potential to improve the water
uptake against the external gradient (Gilbert et al.,
1998; Abd El-Samad et al. 2013). This agree with Sato
et al., (2006) who stated that the increase of some
amino acids might be result of reduced water transport
under saline stress and/ or active physiological
reaction of decreasing the water potential to cope with
