Related Experiment Video
Updated: Jun 17, 2026

Determining Genetic Expression Profiles in C. elegans Using Microarray and Real-time PCR
Published on: July 30, 2011
Transcriptomic Analysis Reveals JAK2/MPL-Independent Effects of Calreticulin Mutations in a C. elegans Model
Ana Guijarro-Hernández1, Laura Eder-Azanza1, Cristina Hurtado1
1Department of Biochemistry and Genetics, School of Sciences, University of Navarra, 31008 Pamplona, Spain.
Abstract:
There is growing evidence that Ph-negative myeloproliferative neoplasms (MPNs) are disorders in which multiple molecular mechanisms are significantly disturbed. Since their discovery, CALR driver mutations have been demonstrated to trigger pathogenic mechanisms apart from the well-documented activation of JAK2/MPL-related pathways, but the lack of experimental models harboring CALR mutations in a JAK2/MPL knockout background has hindered the research on these non-canonical mechanisms. In this study, CRISPR/Cas9 was performed to introduce homozygous patient-like calreticulin mutations in a C. elegans model that naturally lacks JAK2 and MPL orthologs. Whole-genome transcriptomic analysis of these worms was conducted, and some of the genes identified to be associated with processes involved in the pathogenesis of MPNs were further validated by qPCR. Some of the transcriptomic alterations corresponded to typically altered genes and processes in cancer and Ph-negative MPN patients that are known to be triggered by mutant calreticulin without the intervention of JAK2/MPL. However, interestingly, we have also found altered other processes described in these diseases that had not been directly attributed to calreticulin mutations without the intervention of JAK2 or MPL. Thus, these results point to a new experimental model for the study of the JAK2/MPL-independent mechanisms of mutant calreticulin that induce these biological alterations, which could be useful to study unknown non-canonical effects of the mutant protein. The comparison with a calreticulin null strain revealed that the alteration of all of these processes seems to be a consequence of a loss of function of mutant calreticulin in the worm, except for the dysregulation of Hedgehog signaling and flh-3. Further analysis of this model could help to delineate these mechanisms, and the verification of these results in mammalian models may unravel new potential therapeutic targets in MPNs. As far as we know, this is the first time that a C. elegans strain with patient-like mutations is proposed as a potential model for leukemia research.
Insights
This study introduces a new C. elegans model for studying Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs). The model helps investigate CALR mutations independently of JAK2/MPL pathways, revealing new disease mechanisms.
Area of Science:
- Molecular Biology
- Genetics
- Hematology
Background:
- Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) involve complex molecular disturbances.
- CALR mutations drive MPNs via non-canonical pathways, but research is limited by a lack of suitable experimental models.
- Understanding JAK2/MPL-independent mechanisms of CALR mutations is crucial for MPN research.
Purpose of the Study:
- To develop and validate a C. elegans model for studying JAK2/MPL-independent CALR mutation effects in MPNs.
- To identify novel molecular mechanisms and pathways affected by CALR mutations.
- To explore potential new therapeutic targets for MPNs.
Main Methods:
- CRISPR/Cas9 gene editing introduced patient-like CALR mutations into C. elegans lacking JAK2 and MPL orthologs.
- Whole-genome transcriptomic analysis was performed on engineered C. elegans.
- Quantitative PCR (qPCR) validated key transcriptomic alterations.
Main Results:
- Transcriptomic analysis revealed alterations in genes and processes relevant to MPN pathogenesis, independent of JAK2/MPL.
- Identified novel pathways dysregulated by CALR mutations, including Hedgehog signaling and flh-3.
- The observed alterations largely resulted from a loss of function of mutant calreticulin in C. elegans.
Conclusions:
- The C. elegans model provides a novel platform for investigating JAK2/MPL-independent mechanisms of mutant calreticulin.
- This model facilitates the study of previously unrecognized non-canonical effects of mutant calreticulin.
- Further research in this model and validation in mammalian systems may uncover new therapeutic strategies for MPNs.

