Full-length cDNA cloning is a foundational tool for dissecting tumor-associated gene structure, studying transcript variants, and conducting functional characterization. Alfa Cytology specializes in the application and optimization of rapid amplification of cDNA ends (RACE) technology, enabling efficient acquisition of full-length gene sequences from limited RNA samples. Our senior screntists will develop optimal RACE cloning strategies based on your gene information and sample conditions, supporting your entire research path from full-length gene acquisition to functional characterization and transcript analysis.
Rapid amplification of cDNA ends (RACE) is a PCR-based technique used to amplify the complete 5′ and 3′ ends from a known partial cDNA sequence. Its core principle involves designing specific primers based on the known sequence and performing extension amplification toward the unknown ends, thereby obtaining full-length cDNA comprising the complete 5′ untranslated region (5′ UTR), the entire coding sequence (CDS), and the complete 3′ untranslated region (3′ UTR). This technique typically combines reverse transcription, terminal tailing (e.g., TdT-mediated polyC addition) or adapter ligation, supplemented by nested PCR, to enhance amplification efficiency and specificity. In studying gene structure, identifying transcription start sites, and characterizing alternative splicing isoforms at the RNA level, RACE is an indispensable tool. In cancer research, RACE serves as an important tool for obtaining full-length sequences of tumor-associated genes, identifying transcription start sites, cloning alternative splicing isoforms, and dissecting gene structure. Tumor-associated genes often exhibit complex transcriptional regulation and diverse splicing variants, making it difficult to fully resolve their structural features from partial cDNA sequences alone. RACE enables the capture of these critical sequence information from minimal clinical samples or low-abundance transcripts, providing a solid sequence foundation for tumor gene structure annotation, transcriptional regulatory mechanism elucidation, and novel therapeutic target discovery.
Fig. 1 Workflow of the RACE-Nano-Seq protocol. (Tang L, et al.; 2025)
Alfa Cytology's RACE service supports cloning of gene 5′ ends, 3′ ends, and full-length sequences from RNA samples of various sources, applicable to gene structure analysis, transcription start site identification, and alternative splicing studies, providing comprehensive sequence information for tumor gene structure elucidation and functional research. For different research objectives, we offer three options: 5′ RACE, 3′ RACE, and full-length cDNA cloning.
5′ RACE Service
5′ RACE enables precise localization of transcription start sites and 5′ UTR sequences of tumor-associated genes, aiding in the identification of promoter regions and regulatory elements. Key services include:
3′ RACE Service
3′ RACE enables determination of the gene 3′ boundary and polyA tail position, elucidation of transcription termination signals, and analysis of 3′ UTR regulatory function. Services include:
Full-Length cDNA Cloning Service
Full-length cDNA cloning simultaneously covers both 5′ and 3′ ends, providing complete gene material for tumor gene overexpression, protein functional studies, and recombinant protein production. Services include:
| Parameter | Specification |
| RNA source | Cells, fresh tissues, FFPE tissues, blood, etc. |
| RNA requirements | Integrity: RIN ≥ 7 (for fresh samples) / degraded samples may also be attempted |
| Technical methods | 5′ RACE (TdT tailing method / adapter ligation method), 3′ RACE |
| Deliverables | 5′ RACE clones, 3′ RACE clones, full-length cDNA clones, sequencing reports |
| Turnaround time | 3–5 weeks |
| QC | Full-length verification by Sanger sequencing |
Our full-length RACE cloning services enable a wide range of applications in tumor-related gene research, from full-length sequence acquisition and novel gene discovery to transcriptional regulation analysis and functional validation, providing a complete and reliable sequence foundation for downstream studies.
Acquisition of Full-Length Gene Sequences
RACE technology enables the retrieval of full-length cDNA containing complete UTRs and CDS, providing a complete and accurate sequence foundation for target gene cloning and functional studies, ensuring the reliability of subsequent experiments. This is particularly suitable for tumor-related genes with incomplete sequence information.
Novel Gene Discovery
RACE technology allows the cloning of full-length sequences of unknown genes from tumor tissues, providing critical sequence information for the discovery of novel tumor-related genes and potential therapeutic targets, thereby expanding the understanding of tumor driver genes.
Identification of Transcription Start Sites
Precise mapping of gene transcription start sites elucidates promoter regulatory mechanisms, providing key data for dissecting aberrant transcriptional regulation in tumors and promoter activity analysis, and facilitating the identification of abnormally activated transcriptional regulatory events.
Determination of Promoter Regions
Promoter localization is determined through 5′ UTR sequences, providing a basis for promoter activity analysis and transcriptional regulatory mechanism studies, facilitating the functional characterization of tumor-related regulatory elements and the development of targeted regulatory strategies.
UTR Functional Studies
Full-length 5′ and 3′ UTR sequences are obtained to study UTR functions in gene expression regulation, revealing their regulatory roles and underlying mechanisms in tumor initiation and progression, and providing critical sequence support for post-transcriptional regulation research.
Full-Length Gene Cloning
Full-length gene materials are provided for overexpression studies and recombinant protein production, supporting functional validation of tumor targets and protein function research, facilitating downstream applications and translation, and accelerating the research process from sequence acquisition to functional validation.
Project Consultation and Scheme Design
Our scientific team communicates in depth with you to understand your research objectives, gene information, RNA sample types, and downstream application requirements, and designs the optimal RACE cloning scheme.
RNA Extraction and Quality Assessment
Total RNA is extracted from your provided samples, and RNA quality is assessed by electrophoresis and concentration measurement to ensure compliance with RACE experimental requirements.
5′ RACE / 3′ RACE
According to the scheme, reverse transcription, terminal tailing/adapter ligation, and nested PCR amplification are performed to obtain 5′ or 3′ end fragments, which are then cloned into vectors and verified by sequencing.
Full-Length cDNA Cloning and Verification
Based on the 5′ and 3′ sequence information, the full-length sequence is assembled, the full-length cDNA is amplified by PCR, cloned into the destination vector, and verified by full-length Sanger sequencing.
Delivery and Downstream Application Support
Full-length cDNA clones, glycerol stocks, and complete sequencing reports are delivered. If overexpression vector construction or downstream functional studies are required, seamless integration with the corresponding service platforms can be provided.
Alfa Cytology combines a professional full-length cloning platform with rigorous project management and exceptional scientific expertise. Whether you need to obtain the full-length sequence of a gene, identify transcription start sites, or clone alternatively spliced isoforms, we are your trusted partner for accelerating cancer research. Please feel free to contact us to discuss your project.
Reference
For research use only.
Alfa Cytology, a preclinical research solution provider, provides its clients with one-stop solutions to accelerate cancer therapeutics discovery and development.
Copyright © 2026 Alfa Cytology. All rights reserved.
