Puustinen R, Sarvilinna N, Manninen T, Tuohimaa P, Ylikomi T
Department of Cell Biology, Medical School, University of Tampere, FIN-33014, Tampere, Finland.
Eur J Endocrinol. 2001 Sep;145(3):323-33. doi: 10.1530/eje.0.1450323.
Glucocorticoid receptor interacting protein 1 (GRIP1) is a coactivator that binds to the nuclear hormone receptors in a ligand-dependent manner and mediates transcriptional activation of the target genes. The aim of this study was to investigate GRIP1 expression in various murine tissues and whether the protein is nuclear, cytoplasmic, or both.
Two novel polyclonal antibodies against amino acids 34-47 and 468-481 of GRIP1 were raised and characterized in order to study the GRIP1 expression with immunohistochemistry.
Transient transfection studies with COS cells showed a clearly nuclear staining pattern and also immunohistochemical localization of GRIP1 was mainly nuclear, but cytoplasmic expression was seen as well. GRIP1 was expressed in epithelial cells of the submandibular gland, gastrointestinal tract, pancreas, kidney, uterus, mammary gland, testis, prostate, trachea, lungs and adrenal gland. GRIP1 was also detected in stromal cells of colon, rectum, urinary bladder, vagina, uterus, mammary gland and trachea, and to a lesser extent in esophagus, ureter, urethra, thymus and spleen. Smooth muscle cells of the gastrointestinal and urinary tract, uterus, epididymis, prostrate and bronchioles expressed GRIP1. Blood vessels of many organs, capsule of the kidney and prostate, mesovarium, adipocytes of the mammary gland, pericardium and cartilage of the trachea were also GRIP1-positive. Liver, thyroid gland and striated muscle did not express GRIP1.
GRIP1 was expressed in a wide variety of murine organs, and expression varied between cell types and organs. In addition to mainly nuclear localization of endogenous GRIP1, cytoplasmic expression was seen as well.
糖皮质激素受体相互作用蛋白1（GRIP1）是一种共激活因子，它以配体依赖的方式与核激素受体结合，并介导靶基因的转录激活。本研究的目的是调查GRIP1在各种小鼠组织中的表达情况，以及该蛋白是定位于细胞核、细胞质还是两者皆有。
制备并鉴定了两种针对GRIP1第34 - 47位和第468 - 481位氨基酸的新型多克隆抗体，以便用免疫组织化学方法研究GRIP1的表达。
COS细胞的瞬时转染研究显示出明显的细胞核染色模式，GRIP1的免疫组织化学定位也主要在细胞核，但也可见细胞质表达。GRIP1在下颌下腺、胃肠道、胰腺、肾脏、子宫、乳腺、睾丸、前列腺、气管、肺和肾上腺的上皮细胞中表达。在结肠、直肠、膀胱、阴道、子宫、乳腺和气管的基质细胞中也检测到GRIP1，在食管、输尿管、尿道、胸腺和脾脏中表达较少。胃肠道和泌尿道的平滑肌细胞、子宫、附睾、前列腺和细支气管表达GRIP1。许多器官的血管、肾包膜和前列腺包膜、卵巢系膜、乳腺脂肪细胞、心包和气管软骨也呈GRIP1阳性。肝脏、甲状腺和横纹肌不表达GRIP1。
GRIP1在多种小鼠器官中表达，且表达在细胞类型和器官之间存在差异。除了内源性GRIP1主要定位于细胞核外，也可见细胞质表达。
