It was long thought that during an
embryo’s first cell division, one spindle is responsible for segregating the
embryo’s chromosomes into two cells. Scientists now show that there are
actually two spindles, one for each set of parental chromosomes, meaning that
the genetic information from each parent is kept apart throughout the first
A once-maligned genetic parasite may
actually be essential for survival.
Mouse embryos need that genetic
freeloader — a type of jumping gene causing mutations, or transposon, called
LINE-1 — to continue developing past the two-cell stage, researchers reported
Transposons certainly can hop into and
break genes, and cells deploy numerous tools to prevent the jumping genes from
making RNA and protein copies of themselves. But, in early development, LINE-1
is turned on nearly full blast, packing RNA into embryonic cells as well as
“germline” cells, which later give rise to eggs and sperm.
To see what the jumping gene was doing
in the cells, scientists used a short piece of RNA that could pair up with
LINE-1 RNA and cause the transposon to be degraded, essentially turning off the
jumping gene. (The researchers couldn’t simply remove LINE-1 from a cell; there
are thousands of copies) Without LINE-1 RNA, embryonic stem cells stopped
making more of themselves and mouse embryos failed to progress past the
two-cell stage of development. (1)
Look into the ground you step upon.
For mother Earth, life and death were
University of California, Berkeley neuroscientists have tracked the progress of a thought through the brain, showing clearly how the prefrontal cortex at the front of the brain coordinates activity to help us act in response to a perception.
Recording the electrical activity of neurons directly from the surface of the brain, the scientists found that for a simple task, such as repeating a word presented visually or aurally, the visual and auditory cortexes reacted first to perceive the word. The prefrontal cortex then kicked in to interpret the meaning, followed by activation of the motor cortex in preparation for a response. During the half-second between stimulus and response, the prefrontal cortex remained active to coordinate all the other brain areas. (1)
In another research, scientists have unveiled incredible images of how the DNA code is read and interpreted – revealing new detail about one of the fundamental processes of life. Scientists at The Institute of Cancer Research, London, captured images of molecular machinery called RNA Polymerase III in the act of transcribing a gene in exquisite and unprecedented detail. (2)
We apply human-related words to lifeless matter and we believe that this actually means something. The cortex “reacts”, the cortex “interprets”, the cortex “prepares a response”, cells “read” the DNA…
We have created a universe with no humans inside, where only “objects” exist. And then we have given to these objects life. We have not only excommunicated our soul from the universe. We have trapped it inside rocks…
Octopus, squid, and cuttlefish are famous for engaging in complex behavior, from unlocking an aquarium tank and escaping to instantaneous skin camouflage to hide from predators. A new study suggests their evolutionary path to neural sophistication includes a novel mechanism: Prolific RNA editing at the expense of evolution in their genomic DNA.
A paper published last year in Icarus, the prestigious journal of planetary science, asked if it was possible that terrestrial life on Earth had been ‘seeded’ from beyond the Earth – and if so, does the building block of that life, DNA, contain any sort of message from our alien creators. Using mathematics, the authors of the paper – “The “Wow! signal” of the terrestrial genetic code” – looked for evidence of a statistically strong ‘informational’ signal in the genetic code, with surprising results.
The DNA data, according to the paper, display readily recognizable hallmarks of artificiality.
This was not the first time that Icarus had featured a paper entertaining the idea of ‘biological SETI’. In 1979 the journal – under editor Carl Sagan – published a paper titled “Is bacteriophage φX174 DNA a message from an extraterrestrial intelligence?”, written by Japanese biochemists Hiromitsu Yokoo and Tairo Oshima. Given how crazy the idea sounded, Sagan asked a young protégé, David Grinspoon (now a prominent astrobiologist in his own right), to check out the paper to assess whether it was legitimate. (1)
Despite of the outcome – which will need of course more research to validate – what is important is that science can only progress if it analyzes the obvious. Question what is right in front of your, ask about things taken for granted and you shall see miracles. There is no such thing as “junk” (junk DNA). Even the trashiest garbage bin can contain gold…