Correct option is C
The correct answer is (3) Differential RNA processing.
Explanation:
Immunoglobulins (Ig), also known as antibodies, can be synthesized in two forms: a membrane-bound form (which is part of the B cell receptor complex) and a secreted form (which is released into the bloodstream). This flexibility is achieved through differential RNA processing. During the process of RNA splicing, the RNA transcript of the immunoglobulin heavy chain gene can be alternatively spliced to either include or exclude a membrane-binding sequence, allowing the antibody to be expressed either as a membrane-bound form on the surface of B cells or as a secreted form in the plasma. This mechanism allows for the regulation of the type of immunoglobulin based on the needs of the immune system.
Information Booster:
Differential RNA processing involves alternative splicing of RNA transcripts to produce different protein forms.
Membrane-bound immunoglobulins serve as receptors on B cells, while secreted immunoglobulins act as antibodies in the immune response.
The decision to express immunoglobulins as membrane-bound or secreted is made by the cell during the RNA splicing process.
This process is crucial for the functional diversity of antibodies, which are essential for immune recognition and antibody-mediated responses.
RNA splicing provides a mechanism for cells to diversify proteins from a single gene by including or excluding specific sequences.
This mechanism is specific to immunoglobulins and is critical for their role in immune defense.
Additional Information:
Option (1) Allelic exclusion refers to the process by which only one allele of an immunoglobulin gene is expressed in each B cell, ensuring that each B cell produces a single type of antibody.
Option (2) Class switch recombination is a process that changes the constant region of the immunoglobulin heavy chain, allowing a B cell to produce antibodies of different classes (e.g., IgM to IgG), but it does not determine whether the immunoglobulin is membrane-bound or secreted.
Option (4) Codominant expression refers to the expression of both alleles of a gene, such as in the case of the MHC genes but does not apply to the membrane-bound or secreted forms of immunoglobulins.
