X-chromosome helps produce sperm

The supposedly “female” chromosome may have a very male role after all: mediating male infertility and sperm production. The X is also much more rapidly evolving that previously believed, according to research published this week. The researchers came to these conclusions after re-sequencing the existing human X chromosome assembly and comparing it with the X of the mouse, which revealed that while certain regions were highly genetically similar, many others were not shared—a finding that challenged the long held dogma that X-linked genes vary little among mammals. 

Read more: http://bit.ly/16kaJsx

Lentiviral gene therapy

The latest study indicates that lentiviral gene therapy is a safe and effective approach to treat certain diseases. In this method researchers used lentiviruses base, which they have modified not only to improve the efficiency of gene transfer, but also to avoid the activation of cancer-causing genes by loading the vector with self-inactivating promoter sequences that exclusively induce the expression of the therapeutic gene. The researchers transferred a functional ARSA gene into HSCs taken from nine pre-symptomatic MLD patients. Analyses performed 2 years after treatment with the modified HSCs in one patient, and after 18 months in another two patients, revealed that 45–80 percent of the blood cells carried the functional gene. The enzyme was present at normal, healthy levels in these cells and in the cerebro-spinal fluid, where it was completely lacking before. What’s more, long after the symptoms would usually have manifested, the progression of the disease had been stopped in its tracks.

Read more: http://www.the-scientist.com/?articles.view/articleNo/36481/title/Gene-Therapy-Coming-of-Age-/

Controlling genes with light - MIT News Office

A new technology developed at MIT  the Broad Institute that can rapidly start or halt the expression of any gene of interest simply by shining light on the cells. This technique helps the scientists to understand the function of genes better by taking advantage of CRY2 light-sensitive  protein, which changes its shape and binding to CIB1 in the present of light. 

Read more: http://web.mit.edu/newsoffice/2013/controlling-genes-with-light-0722.html

Researchers show that memories reside in specific brain cells - MIT News Office

MIT researchers used Optogenetics to show that memories really do reside in very specific brain cells, and that simply activating a tiny fraction of brain cells can recall an entire memory.

Read more: http://web.mit.edu/newsoffice/2012/conjuring-memories-artificially-0322.html

Image:  An image of a transgenic mouse hippocampus, Source MIT News 

Changes in Astrocytes Shape Result Brain Damage After Traumatic Brain Injury

Astrocytes are star-shaped glial cells which provide structural and metabolic support to neurons and respond to beneficial and detrimental effects in response to neurological trauma. The current research study at University of Bristol suggests brain injury could trigger shape changes in astrocyte cell cultures by altering the genes that controlled actin, a key component of the cytoskeleton. They also identified as yet unknown proteins that were also important in changing astrocyte shape. Given that these astrocyte changes can be both harmful (by preventing the regeneration of nerve cells) or beneficial (by creating a scar that prevents further damage), researchers say they are only beginning to understand the relationship between astrocytes and traumatic brain injury.
Read more: http://bit.ly/1bpkhHs

Journal article: The antagonistic modulation of Arp2/3 activity by N-WASP/WAVE2 and PICK1 defines dynamic changes in astrocyte morphology. Journal of Cell Science, 2013; DOI: 10.1242/jcs.125146

Image: Astrocytes (Blue) and Microglial cells (Red) in hippocampus of the adult rat brain