ISSN 1021-4437, Russian Journal of Plant Physiology, 2009, Vol. 56, No. 2, pp. 264–267. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © P.E. Drobyazina, E.E. Khavkin, 2009, published in Fiziologiya Rastenii, 2009, Vol. 56, No. 2, pp. 291–294.
, are firmly established as the key regu-
lators of the photoperiod-dependent ﬂowering in the
long-day (LD) model plant
Much less is known, however, of genetic control of ﬂo-
ral transition in crop plants, including economically
species, such as potato and tomato.
Previously, the orthologs of
acterized in day-neutral (DN) tomato (
) and short-day (SD)
) [3–6]. In our labo-
ratory, the study of
), disclosed two
genes. These genes were clearly discerned by the exon 2
lengths owing to different numbers of AAC/AAT and
CAA/CAG repeats encoding polyasparagine and poly-
glutamine stretches in COL1 protein [7, 8]. Because of
that, we named these genes short and long (
). The obvious next step was to inquire whether
these genes were expressed.
In this communication, we describe the patterns of
expression in LD/DN
potato, cv. Early Rose. We found that under LD and SD
conditions, both genes displayed characteristic day–
night patterns of expression, although the proﬁles and
amplitudes of expression dramatically differed in two
genes. This evidence presumes that both genes are
functional and probably participate in the photoperi-
odic control of potato development. Such assumption is
supported by the presence of fragments homologous to
in the EST databases.
MATERIALS AND METHODS
Early Rose, an outstanding form of
found in most
pedigrees of early maturing potato cultivars, was bred
from Garnet Chile, which belongs to the LD lowland
Chilean landraces, the reported origin of modern Euro-
pean and North American potato cultivars . Tubers
of cv. Early Rose (VIR24035) were obtained from the
Vavilov Institute of Plant Industry (St. Petersburg).
Plants were grown under two photoperiods (16/8 and
8/16 of light/darkness for LD and SD conditions,
respectively) and room temperature, and young leaves
were sampled for RNA extraction with 2–3-h intervals
within a 24-h period.
RNA extraction and reverse transcription.
extracted from fresh leaves with the TRIzol
(Invitrogen, United States) as recommended by the
Differential Expression of Two
Genes in Potato
P. E. Drobyazina and E. E. Khavkin
Institute of Agricultural Biotechnology, Russian Academy of Agricultural Sciences,
Timiryazevskaya ul. 42, Moscow, 127550 Russia;
fax: 7 (095) 977-0947; e-mail: firstname.lastname@example.org
Received August 14, 2008
gene and its
) orthologs are known to control
the photoperiod-dependent ﬂoral transition in many plant species, the role of these genes in
ment has not been sufﬁciently elucidated. Previously we characterized two forms of
, in potato (
). To prove that these genes were functional,
we followed their expression in potato cv. Early Rose with the real-time PCR technique. Both
displayed characteristic day–night patterns of expression under long-day and short-day conditions. The
proﬁles and amplitudes of expression dramatically differed in two genes, with the maximum
exceeding that of
by an order of magnitude.
Key words: Solanum tuberosum - CONSTANS - ﬂoral transition - gene expression - photoperiodic control -
DN—day-neutral; EST—expressed sequence tag;
T; LD—long day; SD—short day.