mRNA for Microarrays

Utilize Dynabeads Oligo(dT)25 for mRNA microarrays

Dynabeads Oligo(dT)₂₅ are optimal for mRNA isolation in expression profiling applications.

The hybridisation kinetics between mRNA and the Dynabeads are not only fast and efficient, but also comparable to that of free solution hybridisation. This ensures negligible sample loss.

The many types of arrays/chips commercially available require different quantities of mRNA. With Dynabeads, the possibility of scaling the isolation protocols allows you to isolate mRNA from any quantity of cells. This approach can therefore be used to prepare the amount of mRNA required for any type of microarrays, macroarrays, and chips. A few selected examples are: the isolation of mRNA for GeneChip arrays (Affymetrix Inc.) (1,2), for Gene Expression Microarray™ (Incyte Genomics Inc) (3, 4), and for different types of self-spotted arrays (5-11). Dynabeads can also be applied directly in certain electronic chips or microfluidic devices (12).

Figure 1. Functional genomics approach using Dynabeads to find target genes in testicular cancer.Left: Microarray using input mRNA, shows either up- (red) or down- (green) regulated genes in tumour relative to normal testis. Right: Two of the genes were also validated as upregulated at their protein level. Courtesy of R. Skotheim and R. A. Lothe, the Norwegian Radium Hospital, Oslo, Norway.

Dynabeads Oligo(dT)₂₅ mRNA isolation beads target and capture mRNA molecules from a wide range of crude sample types and bypass steps to purify total RNA from mRNA. Other technologies designed to purify total RNA yield ~80% ribosomal RNA (rRNA) and force mRNA to compete with rRNA, transfer RNA, micro RNA, and small cytoplasmic RNA for membrane binding.

Advantages of Dynabeads Oligo(dT)25 beads:

• Fast and gentle procedure yields pure intact mRNA
• Extremely pure mRNA isolation
• Sensitive mRNA isolation from ultra-small starting samples

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11. Frohme M. et al. (2000) Use of representational difference analysis and cDNA arrays for transcriptional profiling of tumor tissue. Ann. N.Y. Acad. Sci. 910:85-104.
12. Fan ZH. et al. (1999) Dynamic DNA hybridization on a chip using paramagnetic beads. Anal. Chem. 71(21):4851-4859.