The effect of column purification on cDNA indirect labelling for microarrays

Quantitative analysis of deadenylation-independent mRNA decay by a modified MBRACE assay

Endonuclease cleavage is the rate-limiting step in the decay of nonsense-containing human β-globin mRNA in erythroid cells. The 5'-truncated intermediates thus generated are polyadenylated and more stable than the parent mRNA. Northern blotting is commonly used to measure the decay rate of full-length mRNA, and S1 nuclease protection is used to assay the fate of decay intermediates. We have adapted the more sensitive and facile MBRACE assay (Lasham et al., Nucleic Acids Res 38: e19, 2010) to quantitatively monitor the decay process by detecting full-length β-globin and its decay intermediates.

Brain tumor cell line authentication, an efficient alternative to capillary electrophoresis by using a microfluidics-based system

BACKGROUND

The current method for cell line authentication is genotyping based on short tandem repeat (STR)-PCR involving coamplification of a panel of STR loci by multiplex PCR and downstream fragment length analysis (FLA), usually performed by capillary electrophoresis. FLA by capillary electrophoresis is time-consuming and can be expensive, as the facilities are generally not accessible for many research laboratories.

METHODS

In the present study, a microfluidic electrophoresis system, the Agilent 2100 Bioanalyzer, was used to analyze the STR-PCR fragments from 10 human genomic loci of a number of human cell lines, including 6 gliomas, 1 astrocyte, 1 primary lung cancer, 1 lung brain metastatic cancer, and 1 rhabdomyosarcoma; and this was compared with the standard method, that is, capillary electrophoresis, using the Applied Biosystems 3130xl Genetic Analyzer.

RESULTS

The microfluidic electrophoresis method produced highly reproducible results with good sensitivity in sizing of multiple PCR fragments, and each cell line demonstrated a unique DNA profile. Furthermore, DNA fingerprinting of samples from 5 different passage numbers of the same cell line showed excellent reproducibility when FLA was performed with the Bioanalyzer, indicating that no cross-contamination had occurred during the culture period.

CONCLUSION

This novel application provides a straightforward and cost-effective alternative to STR-based cell line authentication. In addition, this application would be of great value for cell bank repositories to maintain and distribute precious cell lines.