What is major groove and minor groove?

The minor groove contains the pyrimidine O-2 and the purine N-3 of the base pair, and the major groove is on the opposite side of the pair. The methyl group of thymine also lies in the major groove. In B-DNA, the major groove is wider (12 versus 6 Å) and deeper (8.5 versus 7.5 Å) than the minor groove (Figure 27.8).

What is the function of major groove?

As you noted, the major groove is wider than the minor groove. These grooves allow proteins to bind to and recognize DNA sequences from the outside of the helix. The grooves expose the edges of each base pair located inside the helix, which allows proteins to chemically recognize specific DNA sequences.

What causes major and minor grooves?

The major and minor (19 kb gif) groove arise because of the orientation of the base pairs across the helix. The grooves separate the two sugar-phosphate backbones from each other and the atoms exposed in the grooves are accessible to the solvent and to interactions with proteins.

How do you know if its a major or minor groove?

The major groove occurs where the backbones are far apart, the minor groove occurs where they are close together. The grooves twist around the molecule on opposite sides.

What is a major groove DNA?

The major groove occurs where the backbones are far apart, the minor groove occurs where they are close together. The grooves twist around the molecule on opposite sides. Certain proteins bind to DNA to alter its structure or to regulate transcription (copying DNA to RNA) or replication (copying DNA to DNA).

What binds to the major groove of DNA?

proteins
In general, proteins bind to DNA in the major groove; however, there are exceptions. Protein–DNA interaction are of mainly two types, either specific interaction, or non-specific interaction.

Why is a DNA shorter than B-DNA?

Ø A DNA is 20 to 25% shorter than B-DNA due to the smaller rise per turn. Ø A-DNA contains 11.6 base pairs per turn. Ø The distance between the adjacent base pairs is 2.9 Å. Ø Individual base pairs in A-DNA are 20⁰ tilted with respect to the helical axis.

Does RNA have major grooves?

The common RNA A-form helix is characterized by major and minor grooves that are lined with distinct atomic groups emanating, respectively, from opposite sides of the paired bases. For the common DNA B-form helix, the major groove is wide and will accommodate a polypeptide binding element such as an α-helix.

How is the major groove different from the minor groove?

As the strands are not directly opposite each other, the grooves are unequally sized. One groove, the major groove, is 22 Å wide and the other, the minor groove, is 12 Å wide. The narrowness of the minor groove means that the edges of the bases are more accessible in the major groove.

Why are the bases in the major groove more accessible?

The width of the major groove means that the edges of the bases are more accessible in the major groove than in the minor groove. As a result, proteins such as transcription factors that can bind to specific sequences in double-stranded DNA usually make contact with the sides of the bases exposed in the major groove.

Where are the major and minor grooves located in the helix?

The strand backbones are closer together on one side of the helix than on the other. The major grooveoccurs where the backbones are far apart, the minor grooveoccurs where they are close together. The grooves twist around the molecule on opposite

Which is wider major groove or minor groove in DNA?

The major groove is wider than the minor groove in DNA (Figure 2.5. 2 d ), and many sequence specific proteins interact in the major groove. The N7 and C6 groups of purines and the C4 and C5 groups of pyrimidines face into the major groove, thus they can make specific contacts with amino acids in DNA-binding proteins.