TY - JOUR
T1 - The low-density lipoprotein receptor-related protein 1 (LRP1) interactome in the human cornea
AU - Mogensen, Emilie Hage
AU - Poulsen, Ebbe Toftgaard
AU - Thøgersen, Ida B.
AU - Yamamoto, Kazuhiro
AU - Brüel, Annemarie
AU - Enghild, Jan J.
N1 - Publisher Copyright:
© 2022 The Authors
PY - 2022/6
Y1 - 2022/6
N2 - The human cornea is responsible for approximately 70% of the eye's optical power and, together with the lens, constitutes the only transparent tissue in the human body. Low-density lipoprotein receptor-related protein 1 (LRP1), a large, multitalented endocytic receptor, is expressed throughout the human cornea, yet its role in the cornea remains unknown. More than 30 years ago, LRP1 was purified by exploiting its affinity for the activated form of the protease inhibitor alpha-2-macroblulin (A2M), and the original purification protocol is generally referred to in studies involving full-length LRP1. Here, we provide a novel and simplified LRP1 purification protocol based on LRP1's affinity for receptor-related protein (RAP) that produces significantly higher yields of authentic LRP1. Purified LRP1 was used to map its unknown interactome in the human cornea. Corneal proteins extracted under physiologically relevant conditions were subjected to LRP1 affinity pull-down, and LRP1 ligand candidates were identified by LC-MS/MS. A total of 28 LRP1 ligand candidates were found, including 22 novel ligands. The LRP1 corneal interactome suggests a novel role for LRP1 as a regulator of the corneal immune response, structure, and ultimately corneal transparency.
AB - The human cornea is responsible for approximately 70% of the eye's optical power and, together with the lens, constitutes the only transparent tissue in the human body. Low-density lipoprotein receptor-related protein 1 (LRP1), a large, multitalented endocytic receptor, is expressed throughout the human cornea, yet its role in the cornea remains unknown. More than 30 years ago, LRP1 was purified by exploiting its affinity for the activated form of the protease inhibitor alpha-2-macroblulin (A2M), and the original purification protocol is generally referred to in studies involving full-length LRP1. Here, we provide a novel and simplified LRP1 purification protocol based on LRP1's affinity for receptor-related protein (RAP) that produces significantly higher yields of authentic LRP1. Purified LRP1 was used to map its unknown interactome in the human cornea. Corneal proteins extracted under physiologically relevant conditions were subjected to LRP1 affinity pull-down, and LRP1 ligand candidates were identified by LC-MS/MS. A total of 28 LRP1 ligand candidates were found, including 22 novel ligands. The LRP1 corneal interactome suggests a novel role for LRP1 as a regulator of the corneal immune response, structure, and ultimately corneal transparency.
KW - Cornea
KW - Low-density lipoprotein receptor-related protein 1 (LRP1)
KW - Mass spectrometry (MS)
KW - Protein purification
KW - Protein–protein interaction
UR - http://www.scopus.com/inward/record.url?scp=85129272970&partnerID=8YFLogxK
U2 - 10.1016/j.exer.2022.109081
DO - 10.1016/j.exer.2022.109081
M3 - Journal article
C2 - 35461874
AN - SCOPUS:85129272970
SN - 0014-4835
VL - 219
JO - Experimental Eye Research
JF - Experimental Eye Research
M1 - 109081
ER -