Molecular cloning of cDNA encoding human interleukin-2 receptor

Area of Science:

• Immunology
• Molecular Biology
• Cell Biology

Background:

• The interleukin-2 (IL-2) receptor plays a crucial role in immune responses.
• Understanding the molecular structure of the IL-2 receptor is essential for comprehending T cell activation and function.

Purpose of the Study:

• To purify the human interleukin-2 (IL-2) receptor.
• To determine the N-terminal amino acid sequence and primary structure of the IL-2 receptor precursor.
• To identify the messenger RNAs (mRNAs) encoding the IL-2 receptor.

Main Methods:

• Affinity chromatography using the anti-Tac monoclonal antibody for receptor purification.
• N-terminal amino acid sequencing.
• Isolation and sequencing of complementary DNA (cDNA) clones.
• Northern blot analysis to detect specific mRNAs.
• Expression of the IL-2 receptor in COS cells using cDNA.

Main Results:

• The human IL-2 receptor was successfully purified.
• The N-terminal amino acid sequence was determined.
• The primary structure of the IL-2 receptor precursor was revealed as a 272-amino acid protein.
• A putative 19-residue transmembrane region was identified, separating extracellular and intracellular domains.
• Two mRNAs (1.4 and 3.5 kilobases) encoding the IL-2 receptor were detected in human T cells.
• The cDNA successfully directed the synthesis of the IL-2 receptor in COS cells.

Conclusions:

• The study elucidated the primary structure of the human IL-2 receptor.
• The findings provide a molecular basis for understanding IL-2 receptor function and signaling.
• The identified transmembrane region suggests a mechanism for membrane anchoring and signal transduction.