AnaSpec, Eurogentec Group is pleased to introduce a new long wavelength
fluorimetric assay kit for determining Dipeptidyl Peptidase IV (DPPIV)
activity, the SensoLyte® Rh110 DPPIV Assay Kit. This kit
contains a substrate that emits in the green range of 520 nm when cleaved by DPPIV.
The kit provides a convenient assay for enzyme inhibitors and activators
screening or for the continuous assay of enzyme activity. Cleavage of the fluorogenic
substrate by DPPIV generates the Rh110 (rhodamine 110) fluorophore which has a
bright green fluorescence. Fluorescence can be monitored at excitation/emission=490/520
nm. The longer wavelength spectra and higher extinction coefficient of Rh110 provide
greater sensitivity and less interference from other reaction components.
Dipeptidyl Peptidase IV (DPPIV, DPP-4, CD26) is a cell surface serine protease,
which cleaves Xaa-Pro or less efficiently Xaa-Ala dipeptides from the N-terminus.1-3
DPPIV possesses an identical function to the T-cell surface antigen (CD26).1
DPPIV is commonly found in mammalian tissues and is highly expressed in hepatocytes,
pancreatic epithelial cells, intestinal epithelium, and kidney cortex.3
DPPIV plays an important role in glucose homeostasis by proteolysis of incretins
such as glucagon-like peptide-1 (GLP-1). Due to its role in degradation of GLP-1,
DPPIV is a therapeutic target for type 2 diabetes.
Figure 1. Inhibition of DPPIV activity measured with SensoLyte®
Rh110 DPPIV Assay Kit.
The SensoLyte®AMC DPPIV Assay Kit, which employs an AMC fluorogenic
substrate, is also available from AnaSpec. This kit is optimized for screening
of enzyme inhibitors. This kit contains an AMC labeled substrate that has a
high reactivity and low background. Upon protease cleavage, this substrate generates
the AMC fluorophore emitting bright blue fluorescence that can be monitored
at excitation/emission=354/442 nm. Increase in AMC fluorescence is proportional
to DPPIV activity.
1. Zhu, L. et al, J. Biol. Chem. 278, 22418 (2003).
2. Mentlein, R. Regulatory Peptides 85, 9 (1998).
3. Qi, SY. et al, Biochem. J. 373,