Research on GPR34, which was discovered in 1999 as an orphan G protein-coupled receptor of the rhodopsin-like class, disclosed its physiologic relevance only piece by piece. Being present in all recent vertebrate genomes analyzed so far it seems to improve the fitness of species although it is not essential for life and reproduction as GPR34-deficient mice demonstrate. However, closer inspection of macrophages and microglia, where it is mainly expressed, revealed its relevance in immune cell function. Recent data clearly demonstrate that GPR34 function is required to arrest microglia in the M0 homeostatic non-phagocytic phenotype. Herein, we summarize the current knowledge on its evolution, genomic and structural organization, physiology, pharmacology and relevance in human diseases including neurodegenerative diseases and cancer, which accumulated over the last 20 years.

对GPR34的研究于1999年被发现为视紫红质样类的孤儿G蛋白偶联受体，它仅逐一揭示了其生理相关性。到目前为止，所有最近分析过的脊椎动物基因组中都存在这种抗体，尽管它对生命和繁殖不是必不可少的，但似乎可以改善物种的适应性，如GPR34缺陷小鼠所证明的那样。但是，仔细检查主要表达巨噬细胞和小胶质细胞后，发现其与免疫细胞功能有关。最近的数据清楚地表明，要使小胶质细胞停滞在M0稳态非吞噬性表型中，就需要GPR34功能。在这里，我们总结了有关其进化，基因组和结构组织，生理学，药理学以及与人类疾病（包括神经退行性疾病和癌症）相关性的最新知识，