Deinococcus radiodurans are deep branching bacteria that may retain some remnants of the originally designed cells. The most unusual feature of these bacteria is their incredible ability to survive exposure to massive amounts of ionizing radiation and other extreme physical challenges, something that would have been quite useful for seeding this planet billions of years ago.

The ionizing radiation is typically lethal because it blasts the DNA into fragments and it is extremely difficult for the DNA repair machinery to paste the DNA fragments back together in the correct order. Among humans, exposure to less than 500 rads of ionizing radiation is usually lethal. E. coli are much more resistant, as it usually takes anywhere from 100-200 kilorads to kill them. In comparison, Deinococcus can withstand exposure to more than 1500 kilorads without suffering any deleterious effects. How does Deinococcus do it?

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The cell is the basic unit of life. Yet it is also positioned at the interface between the non-teleological and teleological perspectives. Within the cell is a reality that is extremely friendly to the teleological viewpoint, where sophisticated structures exist for a purpose and function together in a network that elicits life. Yet outside every cell is an environment that seems more friendly to a non-teleological perspective, where contingency dominates, the Blind Watchmaker makes what it will make, and there is no clear purpose. Will the non-teleological perspective of evolution eventually reach into the cell and conform it accordingly? Or will the teleological perspective of the cell eventually reach out into evolution and conform it accordingly?

Retroviruses are unique for their ability to permanently insert their genetic material into the DNA of host cells, he said. During evolution of mammals, some retroviruses infected the germline (cells of the ovary and testis that have genetic material that are passed to their offspring) of the host, which is then inherited by their children. These retroviruses, known as endogenous retroviruses, are present in the genome of all mammals, including humans. Consequently, endogenous retroviruses can be considered remnants of ancient retroviral infections, Spencer said.

Many scientists believed these endogenous retroviruses were junk DNA, he said.

“Indeed, these endogenous retroviruses are usually harmless and generally contain mutations that prevent them from producing infectious retroviruses,” he said.

However, several endogenous retroviruses appear to provide protection from infection and are involved in reproduction. For instance, the exogenous Jaagsiekte Sheep Retrovirus or JSRV causes lung tumors in sheep and led to the death of Dolly, the world’s first mammal cloned from an adult cell. The idea that endogenous retroviruses are important for reproduction in mammals has been around for about 30 years, Spencer said. Studies in cultured cells have shown that a protein of a human endogenous retrovirus might have a role in development of the human placenta. - Here

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The life of a cell is all about growing and dividing at the right time. That is why the cell cycle is one of the most tightly regulated cellular processes. A control system with several layers adjusts when key components of the cell cycle machinery are produced, activated and degraded to make sure that the schedule is kept. These layers of control work differently and are usually studied separately, but researchers at the European Molecular Biology Laboratory (EMBL) and the Technical University of Denmark (DTU) have now discovered that they change in a highly coordinated fashion during evolution. The study, which will be published in this week’s online issue of Nature, also reveals that although most components of the cell cycle have been conserved over one billion years, the temporal regulation of this process has evolved remarkably fast. - Here

The more we learn about biology and evolution, the more it becomes clear that truly innovative solutions to design problems are ancient and deeply embedded. Consider this recent finding:

In higher order animals, genetic information is passed from parents to offspring via sperm or eggs, also known as gametes. In some single-celled organisms, such as yeast, the genes can be passed to the next generation in spores. In both reproductive strategies, major physical changes occur in the genetic material after it has been duplicated and then halved on the way to the production of mature gametes or spores. Near the end of the process, the material – called chromatin, the substructure of chromosomes – becomes dramatically compacted, reduced in volume to as little as five percent of its original volume.

The molecule in question is a phosphorous molecule that modifies a histone. Histones are relatively small proteins around which DNA is coiled to create structures called nucleosomes. Compact strings of nucleosomes, then, form into chromatin, the substructure of chromosomes.

“This molecular mark is required at a critical time leading up to genome compaction in spores and sperm,” says Shelley L. Berger, Ph.D., the Hilary Koprowski Professor at The Wistar Institute and senior author on the study. “Also, there seems to be a similarity in the way the mark is used in organisms as different from each other as yeast and mammals, suggesting that compaction has been important throughout evolution.”

Concepts from engineering continue to produce much fruit in biological research.

From Here -

This feedback loop acts as a sensor that ensures there are sufficient primordial germ cells in the ovary at the end of larval development. The level of EGF signaling is used to keep the amount of germ cells just right, so that there are not too few and not too many of them.

The scientists had a hunch that PGCs and the somatic cells communicate. “Dr. Gilboa’s experiments clearly show there is a feedback mechanism, whereby the PGCs send a signal to the somatic cells to keep them alive and the somatic cells send a signal back to the germ cells, keeping them in check,” says Dr. Lehmann.

Feedback mechanisms and communcation theory are teleological concepts that were imported into biology decades ago. As you can see, these design concepts are now deeply entrenched in the heart of biological research. The reason is simple. If you are to describe advanced technology, you will need technological concepts.

Also, the hypothesis of superficial diversity, something that we’d predict if evolution was front-loaded, continues to make predictions:

Genetics research is revealing commonalities across species; the fruit fly delivers cues. It is an animal in which processes are first discovered and which are later confirmed in humans. “Evolution works–what works for the fruit fly is the same principle that nature has put in place for us,” says Dr. Gilboa.

Ah yes, the design of evolution. So unpredictably predictable.

One of the best scientific animations ever can be found here.

It illustrates the process of leukocyte extravasation, but focuses largely on a protein’s-eye view of the various events that take place inside the cell. You’ll see both the assembly and disassembly of actins and microtubules, the shuttling of the cargo vesicles by the motor protein kinesin, the export of RNA through the nuclear pore complexes, the assembly of ribosomes on the RNA along with translation, the shuttling of ribosomes to the surface of the endoplasmic reticulum, the transport of vesicles to the golgi complex, and the exocytosis and activation of new receptors. Many details are missing and this is only a three minute excerpt from an eight minute animation. Nevertheless, Welcome to the Machines.