I wish to raise the following four questions on human low-density lipoprotein receptor-related protein 4 (hLRP4).

1. What is (are) its ligand(s)?

2. Is the complex consisting of hLRP4 and its ligand(s) endocytosed?

In the following two questions, I assume that the complex is endocytosed and the resultant endosome is translocated to lysosome.

3. Is the endosome a kind of “signaling endosome“?

4. What translocates the endosome to lysosome?

Questions 3 and 4 might remind you of Addendum octavum of “TLR9“, one of my previous postings.