The Top Ten lists in Biology feature papers published during the year
2009 (excluding review articles) that were most cited in current
journal articles indexed by
Clarivate
during a recent two-month period. Papers are ranked according to the
latest bimonthly citation count. The articles below are accompanied by
expert discussion and analysis (including comments from the
papers’ authors) written by Jeremy Cherfas, veteran
scientist-journalist and longtime ScienceWatch.com
contributor.
In investigating the complex workings
of the immune system, researchers are
learning more about a recently
discovered group of T helper
cells--TH-17 cells, so designated
because they produce interleukin 17 in
response to infection and other
challenges to the immune system, along
with being implicated in certain
autoimmune diseases. Recent Hot Papers
clarify the processes by which TH-17
cells are triggered, differentiated,
and assigned to different defensive
roles.
View Article
Two recent studies of the genetic underpinnings of
schizophrenia used microarray analysis to examine
the variant DNA patterns, or so-called “copy
number variants, that are characteristic of the
disease. The observed mutations—for example,
in genes associated with brain development, nerve
axons, and working memory—point to a complex
picture that belies simplistic notions of a
“schizophrenia gene” and underscores
the involvement of numerous factors.
View Article
Three papers poised to enter the Top Ten examine, respectively,
three prevalent and intractable diseases: autism, breast
cancer, and type 1 diabetes. All the papers employ recent
techniques of genome-wide analysis and mapping in order to
provide a fuller picture of specific mutations and links that
give rise to disease. In the case of autism, for example,
analysis points not to particular genes, but to copy number
variations that are not present in the parents of autistic
subjects.
View Article
A team of researchers has produced a three-dimensional atlas of
gene expression in the mouse brain. By painstakingly examining
individual slices of mouse brain and determining gene activation by
in situ hybridization, the researchers have determined specific
locations in which more than 20,000 genes are expressed. The team
further determined that nearly 70% of the genes are expressed in
fewer than 20% of the cells. The atlas also provides insights into
the relationship between cell type and cellular function.
View Article
G protein-coupled receptors are trans-membrane signal receptors
involved in a large range of cellular responses to stimuli,
also serving as targets for upwards of half the therapeutic
drugs currently marketed. Recent work has supplied the crystal
structure of one such receptor, the ß2 adrenergic
receptor. These findings have provided insights into interior
water channels and other structural elements that suggest how
these receptors actually work.
View Article
Recent efforts in biology have centered on a particular
immune-system component known as T(h)-17, one of the immune
system's T helper cells. Specially adapted to fighting bacterial
and fungal diseases, T(h)-17 is also involved in such autoimmune
disorders as psoriasis and rheumatoid arthritis. Biologists are
still unraveling the complex interplay of T(h)-17 with the
cytokines IL-6 and TGF-beta, along with other specifics on how
T(h)-17 cells are differentiated to respond to various immune
challenges.
View Article