The sequence of the first five N-terminal amino acids was determined and was found to be Ala-Arg-His-Thr-Pro.
Activity is determined by the dose-dependant inhibition of Prolactin-stimuled proliferation of Nb2 cells and by high affinity binding of oPLR and other lactogenic hormones.
The protein was lyophilized from a concentrated (1mg/ml) solution with 0.0045mM NaHCO3.
Sterile Filtered White lyophilized (freeze-dried) powder.
Protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280 nm using the absorbency value of 2.48 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).
2. Analysis by RP-HPLC, using a standard solution of PRLr-ECD as a Reference Standard.
Greater than 97.0% as determined by:
(a) Analysis by SEC-HPLC.
(b) Analysis by SDS-PAGE.
It is recommended to reconstitute the lyophilized PRL-R in sterile 18MΩ-cm H2O not less than 100ug/ml, which can then be further diluted to other aqueous solutions.
Lyophilized PRL-R although stable at room temperature for 3 weeks, should be stored desiccated below -18oC. Upon reconstitution Prolactin Receptor should be stored at 4oC between 2-7 days and for future use below -18oC.
For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please prevent freeze-thaw cycles.
