LABORATORY REVIEW
MOLECULAR BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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G protein-coupled receptors
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Receptor tyrosine kinases
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Ligand receptors
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Detailed explanation-1: -Answer: (B) Receptor tyrosine kinases Explanation: i. The binding of a signaling molecule (such as a growth factor) causes two receptor monomers to associate closely with each other, forming a co…
Detailed explanation-2: -Receptor tyrosine kinases (RTKs) conduct biochemical signals via lateral dimerization in thwe plasma membrane, and their transmembrane (TM) domains play an important role in the dimerization process.
Detailed explanation-3: -RTKs are single-pass, type I receptors resident in the plasma membrane. Generally, RTKs are activated through ligand-induced oligomerization, typically dimerization, which juxtaposes the cytoplasmic tyrosine kinase domains [3].
Detailed explanation-4: -Hydrophobic signaling molecules typically diffuse across the plasma membrane and interact with intracellular receptors in the cytoplasm. Many intracellular receptors are transcription factors that interact with DNA in the nucleus and regulate gene expression.
Detailed explanation-5: -One of the most common intracellular signaling pathways triggered by RTKs is known as the mitogen-activated protein (MAP) kinase cascade, because it involves three serine-threonine kinases. The pathway starts with the activation of Ras, a small G protein anchored to the plasma membrane.