The KanMX4 marker is a selection marker gene widely used in molecular biology, particularly in yeast genetics.
It consists of a kanamycin resistance gene from Escherichia coli transposon Tn903 (V00359) fused to a promoter and terminator sequences that are functional in yeast. The gene confers resistance to the antibiotic G418 (geneticin), which allows for the selection of cells that have successfully integrated the KanMX4 marker into their genome.
The most popular version of this resistance gene combines the marker with the promoter and terminator of the translation elongation factor 1α (TEF1) gene of Ashbya gossypii This combination is called “KanMX4”.
This system is especially valuable in gene knockout experiments, where the marker is used to replace or disrupt a target gene, facilitating the study of gene function. The KanMX4 cassette is versatile and can be used in various organisms, making it a powerful tool in genetic engineering and functional genomics. For example, it confers resistance in E. coli to kanamycin.
Wach, A., Brachat, A., Pohlmann, R., Philippsen, P., 1994. New heterologous modules for classical or PCR-based gene disruptions in Saccharomyces cerevisiae. Yeast 10, 1793-808. link
The marker switch (MSW) primers makes a PCR product that is 1333 bp long:
>82_MSW_fwd
TCCTTGACAGTCTTGACG
>83_MSW_rev
GTATAGCGACCAGCATTC