Genetics & Molecular Biology

DNA codes for proteins, and, in doing so, is responsible for many processes that take place in our bodies. An important player in the processes that turn a DNA sequence into a functional protein (see figure 1), is messenger RNA, or mRNA. A recent study, published in Nature, has found a way to artificially modify this mRNA. This changes the ‘building instructions’ of the protein and results in a different protein than the one that was originally coded for.

Figure 1: From DNA to protein. 

(Source: http://www.dna-sequencing-service.com/dna-sequencing/mrna-dna/)

You may have heard that doves mate for life but they are a rarity in bird species.   In most, infidelity is a widespread phenomenon even though for females the costs are high because the cuckolded partners often reduce their parental care and extra lovers also may transmit diseases.

Yet female birds are just as promiscuous as males and researchers from the Max Planck Institute for Ornithology in Seewiesen set out to investigate why.   In a genetic long-term study of zebra finches they found that females inherit the disposition for their infidelity from their fathers.

So men get the blame even when females sleep around?

In 2009, Elizabeth. H. Blackburn, Carol W. Greider and Jack W. Szostak were awarded the Nobel Prize in Physiology or Medicine for their discovery of telomerase, an enzyme that replenishes the telomeres (see figure 1), DNA sequences at the endings of the chromosomes which appear to play a very important role in the aging process. This process, however, is far from being completely elucidated.

Figure 1: Human chromosomes, with the telomeres highlighted. (Source: National Institute of General Medical Sciences)

Recombination, the process by which a molecule of (usually) DNA is broken and joined to another one, is one of the main sources of genetic diversity in sexual organisms. Meiotic recombination takes place during the meiotic division (which gives rise to the gametes), and through the process chromosomes show crossover (see figure 1).

Figure 1: An illustration of crossing over during the meiotic division. 

A cute little bunny has sparked renewed radiation fear in Japan. The rabbit was (allegedly) born near the severely damaged Fukushima Dai-ichi nuclear plant and has no ears (see video).

 

However, attributing this to the accidental radiation release after the tsunami, might be a little too presumptuous. There is no reason why it couldn't be a brith defect caused by other factors than the radiation release at the Fukushima nuclear plant. 
We've all seen Jurassic Park. An ancient petrified piece of tree sap (or amber) is found, containing a mosquito that has been sucking dinosaur blood before its demise. A little bit of this blood is gathered, and from it (Hocus Pocus) real dinosaur DNA is extracted. Not too much later, baby dinosaurs are being born, growing up to become man-eaters.

Science fiction, of course. Or not? 
Protein folding is where the coiled strings of amino acids that make up proteins in all living things fold into more complex three-dimensional structures. Incorrectly folded proteins in humans result in such diseases as Alzheimer's, Parkinson's, Huntington's, emphysema and cystic fibrosis, so developing better modeling techniques for protein folding is a good strategy to assist in creating more effective pharmaceutical treatments for such diseases.  

By understanding how proteins fold, and what structures they are likely to assume in final form, researchers are then able to move closer to predicting their function. 

Figuring out the structure of DNA, and the ongoing research into its workings, have provided scientists with a lot of new knowledge. One of the, perhaps unexpected, new areas of research that have sprouted forth from this knowledge, is the area of DNA computing, where DNA molecules are used to perform computational operations.

Human embryonic stem cell research is limited in the US and Europe but creative researchers have made significant advances  using the existing hESC lines allowed under US federal guidelines along with induced pluripotent stem cells and adult stem cells.

Scientists at Monash University's Immunology and Stem Cell Laboratories (MISCL) say they can now make precursor human stem cells from healthy adult kidneys without working on human embryos at all.
In a complex system you never know what obscure change can modify things that wouldn't seem to be related.  A new study shows that variation of the scavenger receptor class B type 1 gene (SCARB1) involved in regulating cholesterol in the bloodstream also appears to affect progesterone production in women, making it a likely culprit in a substantial number of cases of their infertility.

 The group has developed a simple blood test for this variation of the scavenger receptor class B type 1 gene (SCARB1) but emphasize there is no approved therapy yet to address the problem in infertile women.