# Molecular Boolean analyses of chemokine (C–C motif) receptor 1, α1B-adrenoceptor and arginine vasopressin receptor 1A heteromers

## TL;DR

This study uses a new method to show that multiple receptors can form complexes in human cells, suggesting these complexes may play a role in body functions.

## Contribution

The novel use of MolBoolean analyses to quantify receptor proximity and heteromerization potential in both cell models and human cells.

## Key findings

- 60–70% of receptors in HEK293T cells are close enough to form heteromers.
- 30–50% of receptors in human vascular smooth muscle cells can form heteromers.
- MolBoolean analyses reveal spatial distribution insights of GPCRs in membranes.

## Abstract

We reported previously that many chemokine receptors can form heteromeric complexes with α1B-adrenoceptor (α1B-AR) and arginine vasopressin receptor 1 A (AVPR1A). To gain initial insight into the relative proportions of receptors that may participate in the formation of such heteromers, we performed molecular Boolean (MolBoolean) analyses of receptor-receptor interactions in an expression system and in primary human aortic vascular smooth muscle cells (hVSMCs), utilizing chemokine (C–C motif) receptor 1, α1B-adrenoceptor and AVPR1A as representative receptor partners. In HEK293T cells co-expressing all three receptors, 60–70 % of each recombinant receptor were located proximal enough to permit heteromerization with the other two receptor partners. In primary human vascular smooth muscle cells, 30–50 % of each receptor were located proximal enough to permit heteromerization with the other two receptor partners. The MolBoolean analyses of receptor-receptor interactions provides new insights into the spatial distribution of GPCRs in the plasma membrane. Our finding that large proportions of the receptor partners may be able to participate in heteromerization supports the concept that such hetero-oligomeric complexes composed of CCR1, α1B-AR and AVPR1A could be of physiological relevance.

•MolBoolean analyses were used to assess interactions between CCR1, α1B-adrenoceptor and AVPR1A.•60–70 % of each recombinant receptor were located proximal enough to permit heteromerization with the other receptor partners in HEK293T cells.•30–50 % of each receptor were located proximal enough to permit heteromerization with the other receptor partners in human vascular smooth muscle cells.•MolBoolean analyses provide insights into the spatial distribution of GPCRs.

MolBoolean analyses were used to assess interactions between CCR1, α1B-adrenoceptor and AVPR1A.

60–70 % of each recombinant receptor were located proximal enough to permit heteromerization with the other receptor partners in HEK293T cells.

30–50 % of each receptor were located proximal enough to permit heteromerization with the other receptor partners in human vascular smooth muscle cells.

MolBoolean analyses provide insights into the spatial distribution of GPCRs.