Beta-catenin is a protein that in humans and is encoded by ...



Beta-catenin is a protein that in humans and is encoded by the CTNNB1 gene. In Drosophila, the homologous protein is called armadillo. Β-catenin is a subunit of the cadherin protein complex and has been implicated as an integral component in the Wnt signaling pathway.

HMP SHUNT

The pentose phosphate pathway (also called Phosphogluconate Pathway, or Hexose Monophosphate Shunt [HMP shunt]) is a process that serves to generate NADPH and the synthesis of pentose (5-carbon) sugars.

Protein kinase A is a group of enzymes whose activity is dependent on the level of cyclic AMP in the cell.PKA is also known as cAMP-dependent protein kinase. Protein kinase A has several functions in the cell, including regulation of glycogen, sugar, and lipid metabolism. It is important in regulating cell cycle, along with the protein Cyclin.

Chromosome puffs are diffuse uncoiled regions of the polygene chromosome that are sites of RNA transcription. A Balbiani ring is a large chromosome puff.

Cyclic AMP or Cyclic Adenosine Monophosphate is the second messenger important in many biological actions at the cellular level. It is the chemical messenger is generated in the cell membrane from Adenosine triphosphate or ATP in response to a signal from the first messenger (Hormone). cAMP is used for intracellular signal transduction in many organisms conveying the cAMP dependent pathway.

Pinopodes are small, finger-like protrusions from the uterine endometrium. They appear between day 19 and day 21 of gestational age. This corresponds to a fertilization age of approximately 5 to 7 days, which corresponds well with the time of implantation. They only persist for 2 to 3 days. The development of them is enhanced by progesterone but inhibited by estrogens.

Polytene Chromosome

To increase cell volume, some specialized cells undergo repeated rounds of DNA replication without cell division called Endomitosis, forming a giant Polytene chromosome. Polytene chromosomes form when multiple rounds of replication produce many sister chromatids that remain synapsed together.

Q Banding

Quinacrine mustard, an alkylating agent, was the first chemical to be used for chromosome banding. T. Caspersson and his colleagues, who developed the technique, noticed that bright and dull fluorescent bands appeared after chromosomes stained with quinacrine mustard were viewed under a fluorescence microscope.

Central dogma of molecular biology

The central dogma of molecular biology was first enunciated by Francis Crick in 1958 and re-stated in a Nature paper published in 1970.The central dogma deals with the detailed residue-by-residue transfer of sequential information. It states that information cannot be transferred back from protein to either protein or nucleic acid. In other words, 'once information gets into protein, it can't flow back to nucleic acid.'

Chaperones

Chaperones are proteins that assist the non-covalent folding/unfolding and the assembly/disassembly of other macromolecular structures, but do not occur in these structures when the latter are performing their normal biological functions. The common perception that chaperones are primarily concerned with protein folding is incorrect. The first protein to be called a chaperone assists the assembly of nucleosomes from folded histones and DNA and such assembly chaperones, especially in the nucleus, are concerned with the assembly of folded subunits into oligomeric structures.

Contig

A Contig (from contiguous) is a set of overlapping DNA segments derived from a single genetic source. A Contig is also sometimes defined as the DNA sequence reconstructed from a set of overlapping DNA segments.

DNA polymerase

A DNA polymerase is an enzyme that assists in DNA replication. Such enzymes catalyze the polymerization of deoxyribonucleotides alongside a DNA strand, which they "read" and use as a template. The newly-polymerized molecule is complementary to the template strand and identical to the template's partner strand.

Initiatior (Inr) motif

The Initiatior (Inr) motif is a DNA transcription promoter that is similar in function to the Pribnow box (for prokaryotes) or the TATA box (for eukaryotes). It has the consensus sequence YYAN(T/A)YY,where Y stands for any pyrimidine (cytosine or thymine). Similarly to the TATA box, the Inr motif facilitates the binding of Transcription Factor II D (TBP).

LINEs

Long interspersed nuclear elements are long DNA sequences (>5kb) that represent reverse-transcribed RNA molecules originally transcribed by RNA polymerase II into mRNA (messenger RNA to be translated into protein on ribosomes).

Pair-Rule Gene

Pair-rule gene is a type of gene involved in the development of the segmented embryos of insects. Pair-rule genes are defined by the effect of a mutation in that gene, which causes the loss of the normal developmental pattern in alternating segments.

Reverse transcription

Reverse transcription is the process of making a double stranded DNA (deoxyribonucleic acid) molecule from a single stranded RNA (ribonucleic acid) template. It is called reverse transcription as it acts in the opposite or reverse direction to transcription. This idea was very unpopular at first as it contradicted the Central Dogma of Molecular Biology which states DNA is transcribed into RNA which is translated into proteins. However, in 1970 when the scientists Howard Temin and David Baltimore both independently discovered the enzyme responsible for reverse transcription, named reverse transcriptase, the possibility that genetic information could be passed on in this manner was finally accepted.

Ribozyme

A Ribozyme is an RNA molecule that catalyzes a chemical reaction. Many natural ribozyme catalyze either the hydrolysis of one of their own phosphodiester bonds, or the hydrolysis of bonds in other RNAs, but they have also been found to catalyze the aminotransferase activity of the ribosome.

Sigma factor

A sigma factor (σ factor) is a prokaryotic transcription initiation factor that enables specific binding of RNA polymerase to gene promoters. Different sigma factors are activated in response to different environmental conditions. Every molecule of RNA polymerase contains exactly one sigma factor subunit, which in the model bacterium Escherichia coli is one of those listed below. E. coli has at least eight sigma factors; the number of sigma factors varies between bacterial species. Sigma factors are distinguished by their characteristic molecular weights. For example, σ70 refers to the sigma factor with a molecular weight of 70 kDa.

SINEs

Short interspersed nuclear elements are short DNA sequences ( ................
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