Monday, October 26, 2009

Grasping The (extracellular) Matrix, Location, location, location! and more in my picks of the week from RB

Another week has gone by and some very interesting molbio blog posts have been aggregated to Every week [see my opening post on the matter], I'll select some blog posts I consider particularly interesting in the field of molecular biology [see here to get a sense of the criteria that will be used], briefly describe them and list them here for you to check out.

Note that I'm only taking into consideration the molbio-related blog posts aggregated under "Biology".

Congratulations to everyone who got their post selected.

1) Not too often do we have the chance to read a blog post discussing a research article, written by the first author himself. Nick Anthis at The Scientific Activist comments on his first first-author paper exploring the “important biological process of integrin activation”.

Integrins are transmembrane cell-adhesion molecules that mediate communication between the inside and the outside of the cell. Integrins are instrumental in anchoring cells to the extracellular matrix, and this is ultimately regulated from “within the cell” by direct binding of regulatory proteins, like talin, to the cytoplasmic domains of integrins.
The study reports the “the first structure of talin bound to an authentic full-length beta integrin tail” which leads to a new model of integrin activation.

2) Regulatory T –cells (TReg cells) help control immune responses, playing a key role in immune homeostasis. Interestingly, it has been proposed that these cells facilitate tumors' escape from immune monitoring. Among the various origins of TReg cells, they have been reported to arise in the CD8+ population of T-cells:

“At least some of the CD8 suppressor T cells can arise from apparently-conventional CD8 T cells. That is, you can pull CD8 T cells out of a normal mouse’s spleen, and depending on what those cells see and are exposed to, they could progress to being conventional CTL — killing tumor cells, producing interferon and other cytokines, generally being a destructive force — or they could become suppressor CD8 T cells, and actively prevent that destruction from happening”
Ian York at Mystery Rays of Outer Space discusses a recent article reporting the fascinating finding that “one of the forces that can drive a CD8 T cell into being a suppressor T cell is a tumor”.

3) Several studies have reported that a gene’s position within the nucleus can have a profound impact on its transcriptional activity. Some nuclear neighborhoods appear to harbor active genes, while others are associated with transcriptional repression.
Lucas Brouwers at Thoughtomics discusses an important article from early 2008 describing one of the latter: the nuclear lamina. Through the use of the DNA adenine methyltransferase identification technique, the authors found well-defined lamina-associated domains. Interestingly, these domains are characterized by low levels of transcription. Together with previous evidence, it supports the view of the nuclear lamina as a transcriptionally repressive compartment.

That's it for this week. Stay tuned for more MolBio Research Highlights!

ResearchBlogging.orgSome of the articles discussed in this week's selected posts:

Anthis NJ, Wegener KL, Ye F, Kim C, Goult BT, Lowe ED, Vakonakis I, Bate N, Critchley DR, Ginsberg MH, & Campbell ID (2009). The structure of an integrin/talin complex reveals the basis of inside-out signal transduction. The EMBO journal PMID: 19798053

Shafer-Weaver, K., Anderson, M., Stagliano, K., Malyguine, A., Greenberg, N., & Hurwitz, A. (2009). Cutting Edge: Tumor-Specific CD8+ T Cells Infiltrating Prostatic Tumors Are Induced to Become Suppressor Cells The Journal of Immunology, 183 (8), 4848-4852 DOI: 10.4049/jimmunol.0900848

Guelen, L., Pagie, L., Brasset, E., Meuleman, W., Faza, M., Talhout, W., Eussen, B., de Klein, A., Wessels, L., de Laat, W., & van Steensel, B. (2008). Domain organization of human chromosomes revealed by mapping of nuclear lamina interactions Nature, 453 (7197), 948-951 DOI: 10.1038/nature06947

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