DNA methylation affects important developmental processes in both plants
and animals. The process of methylation of cytosines at C-5 is catalysed by
DNA methyltransferases (MTases), which are highly conserved, both struc-turally and functionally, in eukaryotes. In this study, we identified and
characterized cytosine DNA MTase genes that are activated with the onset
of reproductive development in rice.
We choose the kinesins to illustrate similarities and
diﬀerences between protein family databases. Kinesin
and its relatives are motor proteins that utilize ATP
hydrolysis to move along microtubules in eukaryotic cells.
The motor portion of a kinesin is structurally very similar
to that of the myosin motor, which moves along actin
ﬁlaments, although no sequence similarity is evident
between them. This is an example of likely divergence
from an ancestral fold that is beyond current sequence-
based comparison methods to detect.
Non coding endogenous RNAs were first discovered in the last decade of the previous
century. These new discoveries changed our views of the transcriptome landscape of
plant genomes and paradigms of the regulation of gene expression. With the beginning
of this century, we have witnessed an explosion of studies on small regulatory
RNAs that has yielded a basic understanding of the many types of small RNAs in
diverse eukaryotic species and how they are functioning as RNA–protein complexes
along the RNA silencing pathways.
Cell navigation is the process whereby cells or cytoplasmic extensions are
guided from one point to another in multicellular organisms or, in the case
of unicellular eukaryotic organisms, in the environment. Recent work has
demonstrated that membrane trafficking plays an important role in this
Cells of the budding yeast, S. cerevisiae, have for several decades now been considered
as the prototypic eukaryotic cells, ideally suited to study and uncover many
of the basic phenomena of eukaryotic life.
Population geneticists study the genetic composition and variability of natural
populations as well as the theories that explain this variability in terms of natural
selection, mutation, recombination, genetic drift and gene flow. Population genetics
was first developed among eukaryotes in an attempt to reconcile Darwin’s theory of
evolution by natural selection and Mendelian genetics. When Darwin postulated that
natural selection is the main force of evolutionary change, a great controversy was
Peroxisomes are cell organelles that are present in almost all eukaryotic
cells and involved in a large range of metabolic pathways. The organelles
are highly dynamic in nature: their number and enzyme content is highly
variable and continuously adapts to prevailing environmental conditions.
This review summarizes recent relevant developments in research on pro-cesses that are involved in the regulation of peroxisome abundance and
Lysine-specific demethylase 1 (LSD1) is an enzyme that removes methyl
groups from mono- and dimethylated Lys4 of histone H3, a post-transla-tional modification associated with gene activation. Human LSD1 was the
first histone demethylase to be discovered and this enzymatic activity is
conserved among eukaryotes.
Advanced glycation end-products (AGEs) of DNA are formed spontane-ously by the reaction of carbonyl compounds such as sugars, methylglyoxal
or dihydroxyacetonein vitro andin vivo. Little is known, however, about
the biological consequences of DNA AGEs. In this study, a method was
developed to determine the parameters that promote DNA glycation in
Previous work from this laboratory has shown that the
spectral and functional properties of a prokaryotic xanthine
dehydrogenase fromComamonas acidovoransshow some
similarities to those of the well-characterized eukaryotic
enzymes isolated from bovine milk and from chicken liver
[Xiang, Q. & Edmondson, D.E. (1996) Biochemistry35,
5441–5450]. Therefore, this system was chosen to study the
factors involved in the expression of functional recombinant
enzyme in Escherichia colito provide insights into the
assembly of the functional Mo-pyranopterin center....
The 26S proteasome, a protein complex consisting of a 20S
proteasome and a pair of 19S regulatory particles (RP),
is involved in ATP-dependent proteolysis in eukaryotes.
In yeast, theRP contains six different ATPase subunits and,
at least, 11 non-ATPase subunits. In this study, we identi®ed
the rice homologs of yeast RP subunit genes from the rice
expressed sequence tag (EST) library.
Chapter 1 - Introduction: Themes in the study of life. In this chapter, you should now be able to: Briefly describe the unifying themes that characterize the biological sciences; distinguish among the three domains of life, and the eukaryotic kingdoms; distinguish between the following pairs of terms: discovery science and hypothesis-based science, quantitative and qualitative data, inductive and deductive reasoning, science and technology.
Worldwide, one in five women has a child by the
age of 18. In the poorest regions of the world, this rises to over
one in three women.
Adolescent pregnancies are more likely to occur
among poor, less educated and rural populations.
WHO’s recommendations for reducing early pregnancy are informed by
two graded systematic reviews, three ungraded studies, as well as the
conclusions of an expert panel.
This book is an introduction to the exciting new
field of ecological genomics, for use in MSc courses
and by those beginning their PhD studies.
When we became involved in a national research
programme on ecological genomics, or ecogenomics
as it became known, we realized that information
on this newly emerging subject needed to be
brought together. In order to start up a research
programme in such a new discipline, not only the
students, but also we as teachers, had to get to grips
with the subject.
In eukaryotes, CpG methylation is an epigenetic DNA modification that is
important for heterochromatin formation. Centromere protein B (CENP-B) specifically binds to the centromeric 17 base-pair CENP-B box DNA,
which contains two CpG dinucleotides. In this study, we tested complex
formation by the DNA-binding domain of CENP-B with methylated and
unmethylated CENP-B box DNAs, and found that CENP-B preferentially
binds to the unmethylated CENP-B box DNA.
Eukaryotic genomes are composed of isochores, i.e. long sequences relat-ively homogeneous in GC content. In this paper, the isochore structure of
Arabidopsis thalianagenome has been studied using a windowless technique
based on theZcurve method and intuitive curves are drawn for all the five
chromosomes. Using these curves, we can calculate the GC content at any
resolution, even at the base level.
In this chapter you will learn: State the basic principles of the cell theory, explain how the surface area-to-volume ratio limits cell size, summarize the role of microscopy in the study of cells, identify the components of a human cell and state its function, distinguish between the structure of a prokaryotic cell and that of a eukaryotic cell,...
The purpose of this review is to discuss the effect of natural antioxidant
compounds as modulators of the 20Sproteasome, a multi-enzymatic multi-catalytic complex present in the cytoplasm and nucleus of eukaryotic cells
and involved in several cellular activities such as cell-cycle progression, pro-liferation and the degradation of oxidized and damaged proteins.
Searching the genome sequence ofStreptococcus pneumoniaerevealed the
presence of a single Ser⁄Thr protein kinase genestkP linked to protein
phosphatasephpP. Biochemical studies performed with recombinant StkP
suggest that this protein is a functional eukaryotic-type Ser⁄Thr protein
kinase.In vitrokinase assays and Western blots ofS. pneumoniaesubcellu-lar fractions revealed that StkP is a membrane protein.
Protein histidine phosphorylation in eukaryotes has been
sparsely studied compared to protein serine/threonine and
tyrosine phosphorylation. In an attempt to rectify this by
probing porcine liver cytosol with the phosphohistidine-containing peptide succinyl-Ala-His(P)-Pro-Phe-p-nitro-anilide (phosphopeptide I), we observed a phosphatase
activity that was insensitive towards okadaic acid and