Vector cloning sits right in the middle of molecular biology. Any time you want to move a piece of DNA from “I amplified it” to “I can store, express, or deliver it,” you need a cloning vector. Real time queries for this are “what is a cloning vector,” “cloning vector vs expression vector,” “how to choose a vector for cloning,” and even very specific things like “cloning sgRNA into vector” or “why is pUC19 a good cloning vector.” That tells us two things: the idea is simple, but the real-world choices are many.
This article explains vector cloning in a practical, lab-friendly way. Here are core features every gene cloning vector needs, walk through different types of cloning vectors (plasmid, bacterial, phage, yeast, plant, mammalian), then move into the actual vector cloning steps — restriction–ligation, PCR/TA, TOPO, Gateway, and viral systems.
What Is a Cloning Vector?
A cloning vector is a small, well-characterized DNA molecule that can accept a foreign DNA fragment and maintain it inside a host cell. In other words: it’s a carrier. You take your insert (a gene, cDNA, PCR product, sgRNA cassette), ligate or recombine it into the vector, and then replicate that construct in a host like E. coli.
So if someone asks “what is a cloning vector?” the short answer is: a DNA vehicle used in molecular cloning to move, copy, and store DNA.
This is the backbone of cloning vectors in biotechnology and cloning vectors in recombinant DNA technology — without a stable vector, you can’t build libraries, express proteins, or engineer cells.
Features of an Ideal Cloning Vector
An ideal cloning vector should have:
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Origin of replication (ori):
This tells the host (often E. coli) to copy the plasmid. Without an ori, your plasmid will not be maintained. Different ori give different copy numbers. -
Selectable marker:
Usually an antibiotic resistance gene (ampicillin, kanamycin, chloramphenicol). This tells you select only the bacteria that received the vector. That’s what people mean by “what are selectable markers in cloning vectors.” -
Multiple cloning site (MCS):
Also called a multiple cloning site vector region or polylinker. It’s a short stretch with many unique restriction sites so you can cut the vector and insert your DNA. -
Reporter/screening system:
Many vectors include the lacZ gene in cloning vector so you can do blue/white screening. If your insert disrupts lacZ, the colonies turn white. -
Small size and stability:
A good vector is not too big (easier to transform) and doesn’t rearrange.
So, an ideal cloning vector should have: ori, selectable marker, unique MCS, and a way to screen inserts.
Different Types of Cloning Vectors
Here are types or examples of Cloning vectors
Plasmid Cloning Vector
The most common. Circular DNA, replicates in E. coli. Examples: pUC19, pBR322, pJET, pDrive. Plasmids are the default bacterial cloning vector because they transform easily.
E. coli Cloning Vector
Most plasmid systems are, in fact, E. coli cloning vectors because E. coli is easy to grow, cheap, and well understood.
Bacteriophage as a Cloning Vector
Some DNA fragments are too large for small plasmids. That’s where bacteriophage as a cloning vector comes in.
- Bacteriophage lambda cloning vector can carry bigger inserts and was historically used for genomic libraries.
- M13 phage as cloning vector is useful for generating single-stranded DNA.
Yeast, Plant, and Animal Vectors used when the insert must eventually be expressed or maintained in a eukaryotic system — for example, to study plant genes or to express a mammalian protein.
Viral / Lentiviral Vectors
You included cloning into lentiviral vector, this is not just cloning for storage; this is cloning so you can deliver the DNA into mammalian cells. Lentiviral vectors are built on the same logic as plasmid vectors (ori, marker, MCS), but they are packaged into viral particles for delivery.
So when someone says “cloning vectors in biotechnology,” they can mean any of these, chosen based on host, insert size, and application.
Cloning Vector vs Expression Vector
This is an important search question, here is main difference between cloning vector vs expression vector.
- A cloning vector is optimized to accept and maintain a DNA insert. It cares about easy cloning, high copy number, and simple screening.
- An expression vector is optimized to produce RNA or protein from that insert. It cares about promoters, ribosome binding sites, tags, secretion signals, etc.
So, if someone asks “how to choose a vector for cloning,” the first question is: Am I only storing/amplifying this DNA (use a cloning vector), or do I want to express it (use an expression vector)?
You can clone into a cloning vector first, confirm sequence, and later subclone into an expression vector. That’s exactly why cloning entry vectors exist, especially in recombination-based systems like Gateway.
Practical Cloning Approaches (How We Actually Put DNA into Vectors)
Classic Restriction–Ligation Cloning
- Amplify or obtain insert.
- Digest insert and vector with compatible restriction enzymes.
- Purify.
- Ligate with DNA ligase.
- Transform into competent E. coli.
- Select on antibiotic plates.
- Screen colonies.
These are the core vector cloning steps. This is the “vector cloning protocol” any lab can follow. If you use two different enzymes (one on each side), that becomes directional cloning into plasmid vectors, the insert can only go in one orientation.
TA Cloning Vectors
TA cloning vectors are designed to accept PCR products amplified by Taq polymerase, which add a single A overhang. The vector has a single T overhang. Ligation is quick and doesn’t require restriction enzymes. This is very popular for fast pcr cloning vector workflows.
TOPO Cloning Vector
A topo cloning vector comes with topoisomerase attached to the ends. You just mix your PCR product with the vector and the enzyme ligates it in a single step. It’s fast and great for high-throughput.
pDrive and pJET Cloning Vector
You had pDrive cloning vector and pJET cloning vector , these are commercial plasmid cloning vectors meant for direct PCR product cloning. They often have a selection mechanism (like a lethal gene) so only successful recombinants survive.
Cloning cDNA in Plasmid Vector
After you make cDNA from mRNA, you need to store it, you do cloning cDNA in plasmid vector so you can sequence, express, or share that cDNA. This uses the same MCS-based approach.
Cloning Oligos into Vector
Short regulatory elements, sgRNA cassettes, or barcodes can be ligated directly, that’s cloning oligos into vector. Usually the vector is pre-cut and the oligos are annealed with compatible overhangs.
So far, all of this is standard molecular cloning vectors work, cut, ligate, transform, screen.
Advanced and Specialized Vector Systems
- gateway cloning destination vector
- cloning sgRNA into vector / gRNA cloning vector
- cloning into lentiviral vector
- ORF cloning vectors maps
- Genscript cloning vectors
- Twist cloning vectors
- GMP cloning vector
- MAC cloning vector
- cloning vector database
Gateway / Recombination-Based Cloning
Gateway cloning destination vector systems use site-specific recombination instead of restriction enzymes. You first put your insert into a cloning entry vector, then recombine it into various destination vectors (bacterial, mammalian, tagged, etc.). This is excellent for labs that clone the same ORF into many backbones.
ORF Cloning Vectors Maps
Some companies offer ORF cloning vectors maps, ready-to-use vectors where common genes/ORFs are already cloned, and the map shows the promoter, tag, and restriction sites. This speeds up experiments.
Cloning sgRNA into Vector / gRNA Cloning Vector
For CRISPR work, you often need to insert a 20 bp guide into a backbone that already contains Cas9 or the rest of the CRISPR machinery. That’s cloning sgRNA into vector or gRNA cloning vector. These vectors often have a short placeholder sequence you replace by ligating your guide oligo.
Cloning Into Lentiviral Vector
If the goal is to deliver the construct into mammalian cells, you clone into a lentiviral backbone, produce virus, and transduce cells. Same cloning logic, different downstream use.
Genscript / Twist / GMP / MAC Cloning Vector
- Genscript cloning vectors and Twist cloning vectors refer to vendor-provided backbones that are sequence-verified and often delivered with your gene already cloned.
- A GMP cloning vector is designed or documented to meet manufacturing/clinical requirements — e.g., for cell therapy.
-
MAC cloning vector can refer to vectors tailored for specific cell types or applications (sometimes macrophage-related, sometimes platform-specific)
These are useful to mention because a modern lab may not always build every vector from scratch; they may order from a vendor and then modify.
Cloning Vector Database
A cloning vector database is simply a curated list of published and commercial vectors, often with maps and sequences. Labs check these to avoid rebuilding vectors that already exist.
Why Is pUC19 a Good Cloning Vector?
This is a common test/exam/Google question: why is pUC19 a good cloning vector?
Short answer:
- It’s small (easy to transform).
- It has a high-copy-number origin of replication.
- It contains an MCS within the lacZα gene, enabling blue/white screening.
- It has an ampicillin resistance gene for selection.
So pUC19 perfectly demonstrates the earlier principle: an ideal cloning vector should have ori, selectable marker, and an easy-to-use MCS.
How to Choose a Vector for Cloning
A good decision process is:
-
What host will maintain it?
If it’s E. coli, use a plasmid cloning vector or an E. coli cloning vector. If it’s yeast or plant, pick the corresponding eukaryotic cloning vectors. -
How big is the insert?
Small → plasmid. Bigger → bacteriophage lambda cloning vector or BAC-style vectors. -
Do you need to express it?
If yes, consider whether you need an expression vector, a lentiviral vector, or a mammalian cloning vector. -
Do you need to clone many variants fast?
Then consider Gateway cloning destination vector systems or topo/TA cloning vectors. -
Any regulatory/clinical requirement?
Then you may need a GMP cloning vector or at least a fully documented backbone.
Commonly Asked Questions:
1. What is a cloning vector?
A cloning vector is a small DNA molecule, such as a plasmid or phage, that carries foreign DNA into a host cell so it can be replicated and analyzed.
2. What is the difference between a cloning vector and an expression vector?
A cloning vector is for inserting and maintaining DNA; an expression vector is for producing RNA or protein from that DNA, usually in a specific host.
3. What are the essential components of a cloning vector?
An origin of replication, a selectable marker, and a multiple cloning site. Many also include a lacZ screenable marker.
4. Can bacteriophages be used as cloning vectors?
Yes. Bacteriophage lambda and M13 phage as cloning vector systems can carry larger inserts than many small plasmids.
5. How do TA cloning vectors work?
They have single T overhangs that ligate to PCR products made by Taq polymerase, which add A overhangs.
6. What is directional cloning into plasmid vectors?
It’s cloning with two different restriction sites so the insert can enter in only one orientation.
7. Can I clone sgRNA into a vector?
Yes. Many CRISPR backbones are designed as gRNA cloning vector or “cloning sgRNA into vector” systems where you ligate short guide sequences.
8. What is a cloning entry vector?
It’s the first vector in a multi-vector recombination system (like Gateway) where you park your insert before moving it into destination vectors.
9. Why do people use pJET or pDrive cloning vector?
Because they simplify PCR product cloning and often include positive-selection features.
10. Where can I find maps for common vectors?
You can use a cloning vector database or supplier websites to download ORF cloning vectors maps and annotated plasmid files.
Final note:
The whole logic of vector cloning is simple — keep DNA small, selectable, and easy to modify — but labs customize it according to host, insert, and downstream application.
