C. elegans che-3 Functional Gene Editing Service

Service Overview Precision editing of che-3 in a premier genetic model for sensory cilia, intraflagellar transport and ciliopathy

che-3 encodes CHE-3, the homolog of the cytoplasmic dynein 1b heavy chain DHC1b and of human DYNC2H1. It is expressed in ciliated sensory neurons and provides the minus-end-directed motor that drives retrograde transport from the ciliary tip back to the base.

In living animals, kinesin-II with its cargoes OSM-1 and OSM-6 normally moves back down the cilium at about 1.1 µm/s. Removing CHE-3 abolishes that movement in cilia while leaving transport in dendrites and anterograde IFT intact, which is how its cilium-specific role was established. CD BioSciences delivers custom che-3 alleles — knockouts, motor-domain point mutants, tail truncations, patient-variant knockins and tag knockins — with full genotype verification.

About the Target Gene: che-3 Key biological and practical facts to inform your edit design

Gene symbol	che-3 (Cytoplasmic dynein 2 heavy chain (DHC1b), the retrograde motor of intraflagellar transport)
Protein product	CHE-3 — cytoplasmic dynein 2 heavy chain, the retrograde IFT motor
Mammalian homolog	DYNC2H1; variants cause short-rib thoracic dysplasia (asphyxiating thoracic dystrophy 3 and related forms)
Biological role	CHE-3 is the minus-end-directed microtubule motor that returns IFT material from the ciliary tip to the base. Its identification settled a specific question: in living worms, kinesin-II and two of its cargoes — OSM-1 and OSM-6 — move at about 1.1 µm/s in the retrograde direction along cilia and dendrites. In a che-3 background, that retrograde movement is blocked inside the cilium while remaining normal in the dendrite, and anterograde transport proceeds without disruption. The clean conclusion was that this single dynein is dedicated to retrograde traffic in the cilium specifically, not to axonal or dendritic transport generally.
Loss-of-function phenotype	Sensory cilia become stunted and swollen, and chemotaxis and dye filling fail. There is also a developmental dimension worth planning around: che-3 mutants show altered dauer entry, which is consistent with the general picture that several sensory-neuron inputs converge on the dauer decision. Across organisms the phenotype is remarkably consistent — Chlamydomonas DHC1b, nematode CHE-3 and mouse DYNC2H1 all give short, bloated cilia, and mouse null alleles are embryonic lethal, unlike the nematode.
Why edit it	Retrograde transport is where the IFT cycle closes: whatever goes up has to come back, and recycling of the motor pool depends on it. Because the forward and reverse halves of the cycle are genetically separable here, a che-3 lesion gives you forward transport with no return — which is also exactly the phenotype of loss-of-function in the retrograde-specific IFT-A subunits, giving you a useful internal comparison.
Recommended background	N2 (wild type). Unlike the mouse, null animals are viable, so the analysis does not require conditional configurations. Because dauer entry is affected, we suggest scoring dauer assays separately from ciliary phenotyping and keeping population density and pheromone conditions constant.
Representative allele	Well-characterised classical alleles from the CGC collection plus engineered deletion alleles; custom CRISPR nulls, motor-domain and AAA+ ATPase point mutants, truncations removing the cargo-binding tail, patient-variant knockins, and fluorescent or epitope tag knockins available on request.

Fig. 1 CHE-3, the cytoplasmic dynein 2 heavy chain that carries retrograde intraflagellar transport back down the C. elegans sensory cilium. The highlighted (amber) node marks the editing target.

che-3 at a glance: che-3 removes retrograde traffic inside cilia, leaving anterograde IFT and dendritic transport intact. Editing che-3 alone is a powerful way to dissect CHE-3 function in vivo, with conserved relevance to human DYNC2H1; variants cause short-rib thoracic dysplasia biology.

Our che-3 Editing Strategies Choose the allele that matches your experimental question

Gene Knockout

gRNA-guided Cas9 cutting with NHEJ repair to introduce frameshift indels, generating premature stop codons and null / strong-loss-of-function che-3 alleles.

Knockin & Tagging

Homology-directed repair (HDR) inserts GFP / HA / FLAG or other tags at the che-3 locus for endogenous expression and subcellular localization studies.

Point Mutation

Introduce specific amino-acid substitutions to dissect functional domains and separate catalytic from scaffolding roles of CHE-3.

Conditional & Reporter Alleles

Build tissue-specific, inducible, or temperature-sensitive configurations and reporter lines for spatiotemporal analysis of CHE-3 function.

A motor-domain point mutant is usually more informative than a deletion, because it lets you ask whether dynein-2 has scaffolding functions independent of its ATPase activity. Note that loss of this heavy chain destabilises the rest of the dynein-2 complex in other systems, so if you want to study the motor alone rather than the whole assembly, plan a stabilising or tagged subunit alongside the edit.

Workflow of Our che-3 Editing Service From sequence to validated strain in a streamlined pipeline

Strategy Design

Define target (knockout / knockin / point mutation), select gRNA(s) and HDR template, confirm against the latest genome build.

gRNA Synthesis

Design, validate, and synthesize high-specificity guide RNAs targeting the che-3 locus.

Vector & Template Construction

Build Cas9 / gRNA delivery construct and, for knockin, the homology-arm repair template.

Microinjection

Perform gonadal microinjection of N2 animals with CRISPR components and co-CRISPR selection markers.

Screening & Verification

PCR, Sanger / sequencing, and phenotype confirmation to isolate edited animals and verify alleles.

Delivery & Report

Provide homozygous / balanced che-3 strains plus a full genotype and methods report.

Key Features Why researchers choose CD BioSciences for C. elegans editing

High-efficiency, optimized CRISPR / Cas9 platform for C. elegans.
Whole-process technical traceability and transparent timelines.
Flexible editing: knockout, knockin, tagging, and point mutation.
Full genotype verification before strain delivery.
One-stop model development integrated with our C. elegans portfolio.
Competitive pricing and short turnaround.
Direct access to scientists and prompt inquiry response.
Reliable, convenient global shipping of frozen stocks.

Applications Where a custom che-3 model adds value

Retrograde intraflagellar transport.
Recycling of kinesin motors and IFT particles.
Separation of ciliary from dendritic transport.
Tip clearance and steady-state cilium length.
Short-rib thoracic dysplasia variant modelling.
Dauer entry and sensory control of development.
Chemotaxis and dye-filling behavioural scoring.

Deliverables What you receive with every project

Genetically verified che-3 edited strain(s) (homozygous or balanced).
Detailed genotyping report (editing strategy, allele sequence, verification data).
Methods summary and rearing / storage recommendations.
Optional: crosses into reporter, cilia- and transition-zone marker, and co-CRISPR selection backgrounds.
Optional: phenotype confirmation, cilium morphology, live IFT imaging, dye-filling and chemotaxis analysis support.

Frequently Asked Questions

What type of che-3 allele will I get from a knockout project?

Standard knockout projects deliver a frameshift indel allele predicted to produce a premature stop and a loss-of-function phenotype. We confirm the edit by sequencing and, where relevant, by characteristic phenotype assays.

Can you add a GFP or epitope tag to endogenous che-3?

Yes. Using HDR with a designed repair template, we can insert GFP, HA, or FLAG tags at the C- or N-terminus while preserving endogenous promoter and regulation.

How long does a typical che-3 editing project take?

Timelines vary with editing type and validation needs, but our optimized pipeline and co-CRISPR selection typically shorten turnaround versus conventional approaches. Contact us with your design for a project-specific estimate.

Is the mouse phenotype relevant if the worm survives?

Yes, but read it as quantitative rather than categorical. Mouse Dync2h1 nulls die as embryos, whereas null worms live and give you accessible sensory neurons — that difference is exactly why the nematode is the practical host. The ciliary defect itself translates well: short, bloated cilia appear in Chlamydomonas, nematode and mouse alike, and Hedgehog signalling is disrupted in the mouse mutant. So use the worm for mechanism and the mouse literature for clinical framing, rather than expecting identical organismal severity.

Start Your che-3 Editing Project

CD BioSciences is committed to convenient, efficient, and cost-effective C. elegans model customization. Tell us your target design — knockout, knockin, tagging, or point mutation — and our scientists will respond with a tailored plan and quote.

References
1. Kim H. M., Colaiácovo M. P. CRISPR-Cas9-guided genome engineering in C. elegans. Current Protocols in Molecular Biology, 2016, 115(1): 31.7.1–31.7.18.
2. Signor D., Wedaman K. P., Orozco J. T., Dwyer N. D., Bargmann C. I., Rose L. S., Scholey J. M. Role of a class DHC1b dynein in retrograde transport of IFT motors and IFT raft particles along cilia, but not dendrites, in chemosensory neurons of living Caenorhabditis elegans. Journal of Cell Biology, 1999, 147(3): 519–530.

For research use only.