ISSN 1021-4437, Russian Journal of Plant Physiology, 2006, Vol. 53, No. 1, pp. 10–24. © MAIK “Nauka /Interperiodica” (Russia), 2006.
Original Russian Text © V.G. Ladygin, 2006, published in Fiziologiya Rastenii, 2006, Vol. 53, No. 1, pp. 15–30.
The formation and development of chloroplast
membrane system in mutant plants usually correlates
with the accumulation of chlorophyll . However, the
loss of chlorophyll in pale-green, yellow, and white pea
leaves upon the deﬁciency of mineral nutrients, such as
nitrogen or iron, was also accompanied by the reduc-
tion of the chloroplast membrane system [2, 3].
Studies with plant mutants revealed a number of
nuclear and chloroplast genes controlling biosyntheses
of pigments, proteins, lipids, and other components of
photosynthetic membranes [4, 5]. Mutational changes of
such genes led to chlorophyll anomalies preventing plas-
tid development and their normal functioning [6–8].
The development of thylakoid system and the thyla-
koid spatial arrangement in chloroplasts depend on the
composition of pigment–protein complexes of photo-
systems I and II (PSI and PSII) [9–11]. In mutants lack-
ing reaction center complexes of PSI, the intergranal
thylakoid regions were reduced. Conversely, when the
reaction center complexes of PSII were lost in mutants,
the granal thylakoids underwent unstacking, and the
chloroplast membrane system was transformed to
strands of single well-developed thylakoids [9–12].
A proportional decrease in the content of PSI and
PSII complexes in pale-green
resulted in a partial reduction of entire membrane sys-
tem of the chloroplast, with a retention of both granal
and intergranal thylakoid regions . At the same
time, the loss of PSI reaction center complexes in
mutants caused a predominant reduction of inter-
granal thylakoid regions , which conﬁrmed the het-
erogeneous distribution of the complexes [10, 11].
Unlike pale-green mutants, phenotypically yellow
mutants possess poorly developed chloroplast mem-
brane system that consists of membrane vesicles, single
thylakoids, and occasional small grana [1, 2].
However, direct correlation between chlorophyll
accumulation and chloroplast structure is not universal.
For example, yellow pea leaves, observed upon iron
deﬁciency, contain well-developed thylakoids capable
of forming a number of small grana [2, 3]. This phe-
nomenon could be related to the ability of iron-deﬁcient
chloroplasts to form a high percentage of chlorophyll-
–protein complexes of PSI and PSII reaction centers
. Hence, the formation of thylakoids depends not
only on the amount of chlorophyll but also on chloro-
phyll partitioning into particular pigment–protein com-
plexes (main structural components of the membranes)
during chloroplast biogenesis. The mechanism of thy-
lakoid system formation can be successfully studied
with an example of
mutants featuring genetic
disorders in early stages of chlorophyll biosynthesis.
Reduction of the Chloroplast Membrane System Caused
by Disorders in Early Stages of Chlorophyll Biosynthesis
V. G. Ladygin
Institute of Basic Biological Problems, Russian Academy of Sciences,
Institutskaya ul. 2, Pushchino, Moscow oblast, 142290 Russia;
Received June 30, 2005
mutant of cotton (
L.) was examined with
respect to development and structural organization of the chloroplast membrane system as affected by disrup-
tion of early stages of chlorophyll biosynthesis in the light. The analysis of early chlorophyll precursors showed
that the mutant is unable to synthesize 5-aminolevulinic acid (5-ALA) in the light. The disorders in early stages
of chlorophyll biosynthesis arrested the development of chloroplast membrane system at the stage of vesicles
and single thylakoids. The accumulation of 2–5% chlorophyll in the mutant was related to the formation of
–protein complexes I and II, whereas pigment–protein complexes composing
reaction centers of photosystem I and photosystem II were lacking. It is concluded that the chloroplast mem-
brane system in the mutant with impaired 5-ALA synthesis is incapable of development and is even reduced
upon long-term growing under light.
Key words: Gossypium hirsutum - chloroplasts - pigments - photosystems - structure
: 5-ALA—5-aminolevulinic acid; LHCI and
LHCII—light-harvesting complexes of photosystems I and II;
PSI and PSII—photosystems I and II; RC—reaction center(s).