Scaling analytical RP-HPLC to semi-preparative for fractionation and characterization of pegfilgrastim oxidized variants.

Pegfilgrastim, a 40 kDa PEGylated form of recombinant human granulocyte colony-stimulating factor (rhG-CSF), is a biotherapeutic protein used to treat chemotherapy-induced neutropenia. To ensure the product is safe and effective, stringent monitoring of product-related impurities, particularly those arising from oxidative degradation, is necessary. This study focuses on the isolation and characterization of oxidized variants in pegfilgrastim using a multi-step approach that includes method transfer to semi-preparative High-Performance Liquid Chromatography (HPLC), mass spectrometry, and an in vitro cell-based potency assay (CBPA).

ERG signaling in prostate cancer is driven through PRMT5-dependent methylation of the Androgen Receptor.

The TMPRSS2:ERG gene fusion is common in androgen receptor (AR) positive prostate cancers, yet its function remains poorly understood. From a screen for functionally relevant ERG interactors, we identify the arginine methyltransferase PRMT5. ERG recruits PRMT5 to AR-target genes, where PRMT5 methylates AR on arginine 761.

Different routes of bone morphogenic protein (BMP) receptor endocytosis influence BMP signaling.

Endocytosis is important for a variety of functions in eukaryotic cells, including the regulation of signaling cascades via transmembrane receptors. The internalization of bone morphogenetic protein (BMP) receptor type I (BRI) and type II (BRII) and its relation to signaling were largely unexplored. Here, we demonstrate that both receptor types undergo constitutive endocytosis via clathrin-coated pits (CCPs) but that only BRII undergoes also caveola-like internalization.

Modulation of GDF5/BRI-b signalling through interaction with the tyrosine kinase receptor Ror2.

The brachydactylies are a group of inherited disorders of the hands characterized by shortened digits. Mutations in the tyrosine kinase receptor Ror2 cause brachydactyly type B (BDB). Mutations in GDF5, a member of the BMP/TGF-beta ligand family, cause brachydactyly type C (BDC) whereas mutations in the receptor for GDF5, BRI-b, cause brachydactyly type A2 (BDA2).

Initiation of Smad-dependent and Smad-independent signaling via distinct BMP-receptor complexes.

Background: BMP-2 (bone morphogenetic protein-2) signals via two types of transmembrane serine/threonine kinase receptors (BRI and BRII), which form heteromeric complexes prior to and after ligand binding. Within a BMP-bound receptor complex, BRII transphosphorylates and activates BRI-a for further signaling. We investigated which signaling pathway is initiated by BMP-2 via preformed receptor complexes versus BMP-2-induced signaling receptor complexes.