T03601 Recombinant human HER3(His Tag)

产品信息(Information)：

背景介绍(Background)：

This gene encodes a member of the epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases. This membrane-bound protein has a neuregulin binding domain but not an active kinase domain. It therefore can bind this ligand but not convey the signal into the cell through protein phosphorylation. However, it does form heterodimers with other EGF receptor family members which do have kinase activity. Heterodimerization leads to the activation of pathways which lead to cell proliferation or differentiation. Amplification of this gene and/or overexpression of its protein have been reported in numerous cancers, including prostate, bladder, and breast tumors. Alternate transcriptional splice variants encoding different isoforms have been characterized. One isoform lacks the intermembrane region and is secreted outside the cell. This form acts to modulate the activity of the membrane-bound form. Additional splice variants have also been reported, but they have not been thoroughly characterized. [provided by RefSeq, Jul 2008].

The human epidermal growth factor receptor 3 (HER3) is a pseudo-kinase member of the epidermal growth factor receptor (EGFR) family. The HER3 gene localizes in the long arm of chromosome 12 (12q13.2), encoding a 180 kDa protein. The extracellular domain of HER3 is divided into four subdomains (I–IV): subdomains I and III are leucine-rich β-helical areas responsible for the ligand binding, whereas subdomains II and IV are cysteine-rich regions. In contrast to other EGFR family members, HER3 is not oncogenic when overexpressed alone. However, ubiquitous HER3 expression is detected in various cancers including breast, ovarian, colon, gastric, lung, cutaneous, and pancreatic cancers. High HER3 expression is also linked to disease progression and/or poor prognosis in many cancer types. The preferable dimerization partners for HER3 are EGFR and HER2, followed by lower affinity to HER4. HER3 also dimerizes with some non-EGFR family receptors, including mesenchymal epithelial transition factor (MET) receptor and fibroblast growth factor receptor 2 (FGFR2). Six of 11 HER3 tyrosine phosphorylation sites are direct recruiters of phosphoinositide-3-kinase (PI3K), making HER3 a strong activator for PI3K / protein kinase B (AKT) signaling, important for cancer cell survival. HER3 also activates mitogen-activated protein kinase (MAPK) signaling, stimulating cell proliferation. Other suggested effectors of HER3 include Janus kinases (JAKs) and activators of transcription and proto-oncogene tyrosine-protein kinase SRC signaling pathways involved in signal transduction and increased cell proliferation.

图 HER3信号通路

制剂(Formulation)：

Lyophilized from 0.22 μm filtered solution in PBS，5%mannital，0.01% Tween80 pH7.4. 

质量控制(Quality Control)：

Purity: ≥ 95% as determined by reducing SDS-PAGE.    

Endotoxin: ＜ 0.1 EU/ug  as determined by LAL test.

保存(Storage)：

Use a manual defrost freezer and avoid repeated freeze - thaw cycles.
12 months from date of receipt, -20 to -70℃ as supplied.
1 month, 2 to 8℃ under sterile conditions after reconstitution.
6 months, -20 to -70℃ under sterile conditions after reconstitution.   

FOR RESEARCH USE ONLY

参考文献：

[1] Haikala HM, Jänne PA. 2021. Clin Cancer Res. 27(13):3528-3539.