Part:BBa_K3113050

CD63

CD63 is a protein that belongs to the family of tetraspanins. It is a cell surface receptor for Timp-1 and plays a role in the activation of cellular signaling cascades. CD63 can be used to load RNA or proteins into extracellular vesicles.

Usage and Biology

The CD63-including superfamily of tetraspanins are cell surface associated membrane proteins with four transmembrane domains. CD63 was the first characterized tetraspanin. It is abundantly represented in late endosomes and lysosomes as well as exosomes. The gene, coding for CD63, is located on the human chromosome 12q13. Although the intracellular function of CD63 remains to be established, a number of studies performed in different cell types implicate a role for CD63 in intracellular transport of other proteins.

Characterization

HiBiT Export

We can successfully secrete CD63-containing exosomes from HEK293T cells 48h after transfection as shown in Figure 1. As observed on the image below, exosomes containing the adapter L7Ae are expressed in approximatelly 150 pmols. Most importantly, the secretion efficiency of loaded exosomes is notably higher compared to control samples lacking the CD63-construct and even twice as high as the secretion efficiency of empty exosomes lacking the RNA-binding protein (RBP).

Figure 1: Secretion efficiency of exosomes calculated from HiBiT-measurements. Loaded vesicles containing the adapter L7Ae as well as empty exosomes lacking the RNA binding protein (RBP) were secreted from HEK293T cells with efficiencies of more than 100 pmol of HiBiT-equivalent. In contrast, control samples transfected with mock DNA did not show any secretion. Measurements were performed for n = 6 biological replicates in a 96-well format.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]