Tag Archives: rna

Learning How Viruses Evade the Immune System

photo of Naama Elefant

MicroRNA genes are a class of very tiny genes found in a variety of organisms. First discovered in 1993 and at the time considered relatively unimportant, they are now recognized as major players in diverse biological processes.

MicroRNAs are important regulators of protein production. Proteins, the building blocks of the cell, must be produced precisely at the right time and place. MicroRNAs specifically latch on to other genes (their targets) and inhibit the production of the protein products of these genes. Hundreds of microRNAs have already been discovered, but the identity of their target genes remains mostly unknown and presents a great challenge in the field.

Elefant developed a computer algorithm that predicts the targets of microRNAs. Her algorithm, named RepTar, searches the thousands of genes in the human genome and through sequence, structural and physical considerations detects matches to hundreds of microRNAs.

For her work in this field, Naama Elefant, a student of Prof. Hanah Margalit of the Faculty of Medicine at the Hebrew University and an Azrieli fellow, was named one of this year’s winners of the Barenholz Prizes for Creativity and Originality in Applied Computer Science and Computational Biology. This discovery also was declared by the magazine Nature Medicine as ”one of the ten notable advances of the year 2007.”
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Cell Signals Webcast

Very cool animation, by Cold Spring Harbor Laboratory and Interactive Knowledge, of the working of the inner workings of our bodies as they react to a cut. If you want to get right to the science, skip the first minute. Providing these types of educational animations is a great way for educational institutions to take advantage of technology to achieve their mission in ways not possible before.

It is annoying how many of those “educational” institutions don’t provide such educational material online (and even take material offline that was online). Have they become more focused on thinking and operating the way they did in 1970 than promoting science education? It is a shame some “educational” institutions have instead become focused on looking backward. I will try to promote those organizations that are providing online science education.

Related: Inside Live Red Blood Cells – Universal Blood

Scientists discover new class of RNA

Scientists discover new class of RNA

These new RNAs are named after their distinctive features: Each molecule contains 21 chemical building blocks (or nucleotides), and each begins with the chemical uridine, represented by the letter U (the only RNA nucleotide not also found on DNA). In addition, each of the 5,000 different 21U-RNA molecules comes from one of two chromosomal regions.

Further, “we can predict where additional 21U-RNA genes might reside,” says Bartel, who is also a member of the Whitehead Institute for Biomedical Research and a Howard Hughes Medical Institute investigator. “Combining these predictions with the 5,000 (21U-RNAs) that we experimentally identified, we suspect that there are more than 12,000 different 21U-RNA genes in the genome.” Because each gene typically produces a unique 21U-RNA, a very large diversity of molecules is made.

RNA description from the Nobel Prize site:

When an organism needs to use the data stored in the genome, e.g. to build components of a new cell, a copy of the required DNA part is made. This copy is called RNA and is almost identical to DNA. Just like DNA, RNA is an abbreviated form of a chemical name which in the case of RNA is ribonucleic acid. Unlike the double stranded DNA, RNA is only made up of a single strand. Furthermore, the base T, thymine, is replaced by U, uracil in RNA. This RNA string is used by the organism as a template when it builds protein molecules, sometimes called the building blocks of the body. For example, your muscles and hair are mostly made up of proteins.

Related: DNA-RNA-Protein Introduction