This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
Odorant binding protein
From Proteopedia
| Line 17: | Line 17: | ||
==== BmorPBP Function ==== | ==== BmorPBP Function ==== | ||
| - | Despite three decades of intensive research, the exact roles of OBP and the mechanism by which the odorant receptor (OR) is activated are still in dispute <ref>DOI: 10.1146/annurev-ento-120811-153635</ref><ref>DOI: 10.1007/s00359-009-0461-4</ref>. | + | Despite three decades of intensive research, the exact roles of OBP and the mechanism by which the odorant receptor (OR) is activated are still in dispute <ref>DOI: 10.1146/annurev-ento-120811-153635</ref><ref name="kaissling 2009">DOI: 10.1007/s00359-009-0461-4</ref>. |
| + | |||
Of all, the role of OBP as an odorant carrier is generally accepted. | Of all, the role of OBP as an odorant carrier is generally accepted. | ||
| Line 50: | Line 51: | ||
This theory is supported by few assumptions. First, it has been found that the BmPBP conformation is changing from its [["open form" (A)]] to the [["close form" (B)]] in a pH dependent manner <ref>DOI: 10.1074/jbc.274.43.30950</ref>, and that the two conformations has different ligand affinities. | This theory is supported by few assumptions. First, it has been found that the BmPBP conformation is changing from its [["open form" (A)]] to the [["close form" (B)]] in a pH dependent manner <ref>DOI: 10.1074/jbc.274.43.30950</ref>, and that the two conformations has different ligand affinities. | ||
| - | Second, the surface of the dendrite is negatively charged <ref>DOI: 10.1016/0040-8166(84)90004-1</ref>, which cause the accumulation of positively charged kations near the membrane surface (20-50 nm), thereby inducing a low pH environment near the dendrite membrane | + | Second, the surface of the dendrite is negatively charged <ref>DOI: 10.1016/0040-8166(84)90004-1</ref>, which cause the accumulation of positively charged kations near the membrane surface (20-50 nm), thereby inducing a low pH environment near the dendrite membrane <ref name="Kissling 2009" /><ref> |
Revision as of 08:53, 8 January 2015
Contents |
Introduction
Odorant-binding protein (OBP) are soluble proteins which involve in the processes of odorant detection in the olfactory sensilla.
The first OBP that was identified is Bovine odorant binding protein, that was isolated from a cow's mucus ref. OBP in vertebrates
OBP in insects
In order to explain the structure and function of these fascinating proteins, this page will further focus on a particular OBP - the well investigated Bombyx mori PBP: BmorPBP.
PBP
PBPs are specialized members of the insect odorant-binding protein (OBP) super-family, and they are categorized into three groups by their lengths: the long-chain PBPs (∼160 aa), the medium-chain PBPs (∼120 aa), and the short-chain PBPs (∼110 aa)
Bombyx mori BmorPBP (lets talk about sex..)
BmorPBP Function
Despite three decades of intensive research, the exact roles of OBP and the mechanism by which the odorant receptor (OR) is activated are still in dispute [1][2].
Of all, the role of OBP as an odorant carrier is generally accepted.
A few functions have been suggested for OBP: 1. 2. 3. 4.
| |||||||||||
Protein conformations
Receptor activation i lepidoptora
- The pH dependent theory
This theory is supported by few assumptions. First, it has been found that the BmPBP conformation is changing from its "open form" (A) to the "close form" (B) in a pH dependent manner [3], and that the two conformations has different ligand affinities.
Second, the surface of the dendrite is negatively charged [4], which cause the accumulation of positively charged kations near the membrane surface (20-50 nm), thereby inducing a low pH environment near the dendrite membrane [5][6]
Proteopedia Page Contributors and Editors (what is this?)
Nurit Eliash, Michal Harel, Joel L. Sussman, Alexander Berchansky, Jaime Prilusky
