Biology Reference
In-Depth Information
Fig. 3
Protein dynamics during cold treatment of
A. thaliana
seeds. Proteins were isolated from mature, dry,
dormant seeds of
A. thaliana
and compared with proteins from seeds incubated for 2 days at 4 °C, using DIGE.
A total protein fraction was isolated as described by Schober et al. [
90
] with minor modifi cations. Proteins from
dormant seeds were labeled with Cye 3, and proteins from cold treated seeds were labeled with Cye 5. The
combined proteins were separated as described in the legend for Fig.
3
. Proteins that are equally abundant in
the two treatments appear as
yellow dots
. Proteins more abundant in the dormant seeds appear
green
and
those more abundant after cold treatment appear
red
2.3 Genetic
Uniformity
Not surprisingly, most seed proteomics research has addressed
agricultural crop plants. Typically these seeds are obtained from a
commercial source, and it is reasonable to assume that they are
genetically uniform so results will not be biased by the contribu-
tions of a “contaminating” proteome. This important point is
often overlooked, however there are reports of substantial differ-
ences between samples of a common species that are distinct culti-
vars/genotypes [
38
,
39
].
The issue of genetic uniformity is much more serious during
analyses of non-cultivated plants. In a few exceptional instances
there are repositories for weed/wild seeds.
A. thaliana
, for exam-
ple, has become such a common experimental system that geneti-
cally uniform cultivar/ecotype seeds are readily available (e.g., the
Arabidopsis Biological Resource Center;
http://abrc.osu.edu/
home
). With soybeans or maize, the wild progenitors of extant
crop plants,
G. soja
and
Z. diploperennis
, respectively, have been
used in genetics and genomics programs, and there are sources for
uniform wild seeds (e.g., USDA Soybean Germplasm Collection,
http://www.ars.usda.gov/is/np/SoybeanGermplasm/Soybean
GermplasmIntro.htm; USDA/ARS Maize Germplasm Collection,
http://www.ars-grin.gov/cgi-bin/npgs/html/crop.pl?89
)
.
