Ballesteros-Weinstein system

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Schematic representation of the structure and numbering of the transmembrane domains of a GPCR using the example of rhodopsin

In biochemistry, the Ballesteros-Weinstein system is a method for numbering positions in G-protein-coupled receptors (GPCR).

properties

The GPCR differ for evolutionary reasons, but still have characteristic amino acids at certain positions in their amino acid sequence . However, these positions are often slightly offset. The universal numbering makes it easier to compare the positions. The method was published in 1995 by Juan A. Ballesteros and Harel Weinstein.

In the Ballesteros-Weinstein system, the single-letter code of an amino acid and the two codes N1 and N2 are used. The two codes N1 and N2 are separated by a period. N1 indicates the position of the transmembrane domain under consideration , counting from the N terminus , i.e. the first transmembrane domain, the second, third, etc. The second code number N2 indicates the position relative to the most conserved amino acid in the transmembrane domain under consideration, which is defined by position 50 becomes. In the direction of the N terminus, this number decreases by one with each amino acid; in the direction of the C terminus it increases accordingly. Occasionally, the position relative to the N terminus is also given in brackets below. For example, a proline (P) at position 267 as the most conserved amino acid in the sixth transmembrane domain of a protein results in the designation P6.50 (267).

An alternative to the Ballesteros-Weinstein system is the Baldwin system.

Individual evidence

  1. Juan A. Ballesteros, Harel Weinstein: Integrated methods for the construction of three-dimensional models and computational probing of structure-function relations in G protein-coupled receptors . In: Methods in Neurosciences , Volume 25, 1995, pp. 366-428 doi: 10.1016 / S1043-9471 (05) 80049-7 .
  2. ^ JM Baldwin: The probable arrangement of the helices in G protein-coupled receptors. In: The EMBO journal. Volume 12, Number 4, April 1993, pp. 1693-1703, PMID 8385611 , PMC 413383 (free full text).