Genetics & Molecular Biology

Though the mechanism responsible for generating part of the skeletal support for the membrane in animal cells is not yet understood, researchers have found a well-defined layer beneath the cell outer membrane forms beyond a certain critical level of stress generated by motor proteins within the cellular system. Active gels are ideal for modeling the similar material found in living cells' structure, made of a dynamic, filamentous scaffold. They are composed of components that take up energy and do directed work. Indeed, chemical energy is fed into the cells' constituents and is transformed…

A few brief days in embryonic life lays out our body's construction plan. The appearance of limbs and vertebrae is orchestrated by a family of 'architect' genes called Hox, each providing precise instructions at a given time. New research has demonstrated that these genes were aligned within our chromosomes according to the order of structures - collinear expression in developing limb buds: first the components of the shoulder, then the arm, and finally the fingers. The cluster of Hoxd genes coordinates the operations of limb formation, in particular. These genes are transcribed in two…

What with all the current talk of GMOs, I would remind folks here that some 20th century methods also raised fears.  A more “traditional” method has been to double the chromosome content of plants — one well known example is Triticale is the hybrid of wheat (Triticum turgidum) and rye (Secale cereale).  This, of course, should be familiar to those who remember the Star Trek episode “The Trouble With Tribbles”.  When crossing wheat and rye, wheat is used as the female parent and rye as the male parent (pollen donor). The resulting hybrid is sterile, and must be treated with…

Female mosquitoes are predators of mammalian blood, relying on blood proteins to lay their eggs. While certain mosquito species are attracted to mammals by their emission of body heat and carbon dioxide, other species, such as Anopheles gambiae and Aedes aegypti, have evolved a strong lust for the smell of humans. Such mosquitoes are also deadly vectors that contribute to the efficient spread of human diseases such as malaria, Dengue hemorrhagic fever, West Nile fever, and chikungunya, with the latter two commonly known as urban epidemics.   Given the role of mosquitoes as vectors of…

Rogue wheat is growing in wheat fields in 127 countries around the world! Should consumers be concerned? Ok, I'm indulging in a poor imitation of the emotive language common in sensational writings about food issues. What I said in the paragraph above is all true, it's just misleading because of a lack of context. After the "crisis" of glyphosate tolerant wheat being found in an Oregon field, I thought it would be useful to put that event into perspective.  So... Wheat 1.0 Wheat is largely a "saved seed crop," meaning that farmers set aside some of the grain from each harvest…

Mouse studies have determined that a small molecule called natriuretic polypeptide b (Nppb) released in the spinal cord triggers a process that is later experienced in the brain as the sensation of itch.  Nppb streams ahead and selectively plugs into a specific nerve cell in the spinal cord, which sends the signal onward through the central nervous system. When Nppb or its nerve cell was removed, mice stopped scratching at a broad array of itch-inducing substances. The signal wasn’t going through. Because the nervous systems of mice and humans are similar, the scientists say a comparable…

Western Europe is a major net importer of food averaging 59 million metric tons during the years 2001 to 2010. That amount is similar to the net imports of all of Africa - a region with 2.5 times as many people. On a per capita basis that represents 139 kg or 290 pounds per person per year. Global food demand is expected to require a 60% increase by 2050, and it will be a major challenge to meet that demand.  Europeans will be increasingly competing with poorer, import-dependent nations. Of course my question about feeding Europe is merely academic. As long as their money is good (at…

Camels, valuable in desert regions throughout the world because of their ability to carry heavy loads over long distances without food or water, are divided into two species, the one-humped dromedary and the two-humped Bactrian camel. Despite the extremely arid conditions where they are popular, camels also still provide enough milk for human consumption and also have an important role as a source of meat. Camels are specialists when it comes to adapting to the environment. Some characterize them as sustainable food producers.  Pamela Burger and colleagues are interested in the…

There are some really cool improvements coming along in several crops that have been developed using the tools of biotechnology - GMOs if you will. Some of these innovations have consumer health benefits. Some expand ways to encourage greater produce consumption. Some reduce food waste. Some prevent crop losses through disease and reduce the need for copper sprays. These traits represent an expansion of biotech beyond the major row crops primarily grown for animal feed or for fiber to crops like apples, oranges, tomatoes, pineapples and potatoes. Whether these new options actually make it…

Decades of focus on genes may have led the scientific community away from a balanced exploration of the organisms that those genes define - whether they be plants, animals or microorganisms - and more toward gene-focused directions: inward, toward the world of cellular and molecular biology, and outward, toward the broad-scale evolutionary issues of population and quantitative genetics. We've become too genetic variation heavy. Obviously genetic variation alone does not adequately explain the intricate variations in the physiology and behavior of complex organisms so authors writing in…