A novel and rapid cloning method for the T-cell receptor variable region sequences

Area of Science:

• Molecular Biology
• Genetics
• Biotechnology

Background:

• Conventional polymerase chain reaction (PCR) necessitates known sequences at both ends of the target DNA for amplification.
• This limitation hinders the amplification and study of DNA fragments with only one known end sequence, such as novel gene discovery or full-length complementary DNA (cDNA) cloning.

Purpose of the Study:

• To develop and validate a novel PCR-based method for amplifying DNA fragments when only one end sequence is known.
• To demonstrate the utility of this method for generating libraries of specific cDNA fragments, exemplified by T-cell receptor (Tcr) alpha-chain amplification.

Main Methods:

• Preparation of blunt-ended double-strand cDNA.
• Circularization of cDNA using T4 DNA ligase to create a PCR template.
• Design of outward-hybridizing PCR primers targeting the known sequence region to amplify unknown flanking sequences.

Main Results:

• Successful amplification and cloning of T-cell receptor (Tcr) alpha-chain cDNA from human peripheral lymphocytes.
• Generation of a Tcr-specific cDNA library containing 1-2 x 10^6 clones.
• Demonstration of the method's effectiveness for amplifying unknown DNA sequences adjacent to a known region.

Conclusions:

• The developed PCR technique enables efficient amplification of DNA fragments with single-end sequence information.
• This method is valuable for cloning full-length cDNA and identifying new gene family members with conserved domains.
• It offers a significant advancement over conventional PCR for specific molecular biology applications.