The full form of rNTP is ribonucleotide triphosphate.
rNTPs are the building blocks of RNA (ribonucleic acid). They are essential for RNA synthesis during transcription. Let's break down what they are composed of:
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Ribose Sugar: rNTPs contain a ribose sugar molecule. This distinguishes them from dNTPs (deoxyribonucleotide triphosphates), which contain deoxyribose sugar.
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Nitrogenous Base: rNTPs include one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), or uracil (U). These bases are attached to the 1' carbon of the ribose sugar.
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Triphosphate Group: rNTPs possess a triphosphate group, meaning three phosphate groups are linked together. These phosphates are attached to the 5' carbon of the ribose sugar via phosphodiester bonds. The energy released by breaking the bonds between these phosphate groups drives the polymerization reaction during RNA synthesis.
During transcription, RNA polymerase selects rNTPs that are complementary to the DNA template strand and joins them together to form a new RNA strand. The two terminal phosphate groups are cleaved off during this process, releasing energy and forming a phosphodiester bond between the remaining phosphate group and the 3' hydroxyl group of the preceding nucleotide in the RNA chain.
In summary, ribonucleotide triphosphates (rNTPs) are the energy-rich precursors used by RNA polymerase to synthesize RNA.
