Question

In northern hybridization probe hybridization forms?

Answer 1

In molecular biology, a hybridization probe is a fragment of DNA or RNA of variable length (usually 100–1000 bases long) which can be radioactively labeled. It can then be used in DNA or RNA samples to detect the presence of nucleotide sequences (the DNA target) that are complementary to the sequence in the probe. The probe thereby hybridizes to single-stranded nucleic acid (DNA or RNA) whose base sequence allows probe–target base pairing due to complementarity between the probe and target.[1] The labeled probe is first denatured (by heating or under alkaline conditions such as exposure to sodium hydroxide) into single stranded DNA (ssDNA) and then hybridized to the target ssDNA (Southern blotting) or RNA (northern blotting) immobilized on a membrane or in situ. To detect hybridization of the probe to its target sequence, the probe is tagged (or "labeled") with a molecular marker of either radioactive or (more recently) fluorescent molecules; commonly used markers are 32P (a radioactive isotope of phosphorusincorporated into the phosphodiesterbond in the probe DNA) or Digoxigenin, which is a non-radioactive, antibody-based marker. DNA sequences or RNA transcripts that have moderate to high sequence similarity to the probe are then detected by visualizing the hybridized probe via autoradiography or other imaging techniques. Normally, either X-ray pictures are taken of the filter, or the filter is placed under UV light. Detection of sequences with moderate or high similarity depends on how stringent the hybridization conditions were applied—high stringency, such as high hybridization temperature and low salt in hybridization buffers, permits only hybridization between nucleic acidsequences that are highly similar, whereas low stringency, such as lower temperature and high salt, allows hybridization when the sequences are less similar. Hybridization probes used in DNA microarrays refer to DNA covalently attached to an inert surface, such as coated glass slides or gene chips, to which a mobile cDNA target is hybridized.

Depending on the method, the probe may be synthesized using the phosphoramidite method, or it can be generated and labeled by PCRamplification or cloning (both are older methods). In order to increase the in vivo stability of the probe RNA is not used, instead RNA analogues may be used, in particular morpholino- derivatives. Molecular DNA- or RNA-based probes are now routinely used in screening gene libraries, detecting nucleotide sequences with blotting methods, and in other gene technologies, such as nucleic acid and tissue microarrays.

Answer 2

Answer:

Explanation:

In chemistry, orbital hybridisation (or hybridization) is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory.sp hybridisation- The intermixing of one s orbital and one p orbital of an atom to produce two new sp hybridised orbitals of equivalent energy is called sp hybridisation. sp3 hybridisation- the intermixing of one s orbital and three p orbitals of an atom to produce four new sp3 hybridised orbitals of equivalent energy is called sp3 hybridisation. sp2 hybridisation- the intermixing of one s orbital and two p orbitals of an atom to produce three new sp2 hybridised orbitals of equivalent energy is called sp2 hybridisation. sp3d hybridisation- this type of hybridistion involves the mixing of one s, three p and one d orbital resulting in the formation of five equivalent sp3d hybrid orbitals. sp3d2 hybridisation- this type of hybridisation involves the intermixing of one s orbital, three p and two d orbitals resulting in the formation of six equivalent sp3d2 hybrid orbitals.