XBP1 Antibodies

Structure of XBP1

XBP1 is a key transcription factor with a molecular weight of approximately 34 kDa. This protein belongs to the basic leucine zipper protein family, and its molecular weight varies among different splicing isomers.

The XBP1 protein contains 261 amino acids, and its basic structure includes the N-terminal transcriptional activation domain, the central DNA binding domain, and the C-terminal leucine zipper dimerization interface. The uniqueness of this protein lies in the atypical splicing mechanism of its mRNA mediated by IRE1α - cutting off 26 nucleotides causes the reading frame to shift, generating an active isomer composed of 376 amino acids. The C-terminal structure of the protein undergoes significant changes after splicing, forming a stable transcriptional activation conformation that can specifically bind to the DNA sequence of the endoplasmic reticulum stress response element UPRE.

Fig. 1 Structural differences between the two splicing isoforms of XBP1.¹

Key structural properties of XBP1:

• Basic leucine zipper (bZIP) DNA binding domain
• Endoplasmic reticulum stress sensing activation domain
• Atypical mRNA splicing sites (26-nucleotide characteristic sequences)
• The dimerization interface at the C-end is regulated to determine the location signal

Functions of XBP1

The core function of the XBP1 gene is to regulate the endoplasmic reticulum stress response. However, this gene is also involved in a variety of cellular processes, including immune differentiation, metabolic regulation and cell fate determination.

The activity of XBP1 is precisely regulated by its unique mRNA splicing mechanism - IRE1α -mediated atypical splicing removes 26 nucleotides, causing the coding box to shift and generating a stable transcriptional active form. This molecular switching property enables it to rapidly respond to changes in intracellular homeostasis and perform fine regulation.

Applications of XBP1 and XBP1 Antibody in Literature

1. Zhao, Yahui, et al. "XBP1 regulates the protumoral function of tumor-associated macrophages in human colorectal cancer." Signal Transduction and Targeted Therapy 6.1 (2021): 357. https://doi.org/10.1038/s41392-021-00761-7

The article indicates that in colorectal cancer, the activation of macrophage XBP1 promotes tumor growth and metastasis. It inhibits the phagocytic function of macrophages by up-regulating cancer-promoting factors such as IL-6 and enhancing "don't eat me" signals such as SIRPα. Targeting XBP1 can reshape macrophage activity, providing a new therapeutic strategy.

2. Lv, Wenhao, et al. "The Role of XBP1 in bone metabolism." Frontiers in Endocrinology 14 (2023): 1217579. https://doi.org/10.3389/fendo.2023.1217579

The article indicates that the transcription factor XBP1 is a key molecule regulating bone metabolism. It plays a significant role in bone diseases such as osteoporosis by influencing the differentiation and function of osteoclasts and osteoblasts, and regulating the intervention of immune cells in the bone remodeling microenvironment. Targeting XBP1 may offer new ideas for the treatment of bone metabolism diseases.

3. Luo X, Alfason L, et al. "Spliced or unspliced, that is the question: the biological roles of XBP1 isoforms in pathophysiology." International Journal of Molecular Sciences 23.5 (2022): 2746. https://doi.org/10.3390/ijms23052746

The article indicates that XBP1 is a key factor in endoplasmic reticulum stress, and its spliceosome XBP1-S regulates unfolded protein responses and participates in tumor progression. Its unspliced body XBP1-u is equally important and can affect autophagy and tumorigenesis through post-translational regulation. Abnormal functions of both are closely related to a variety of diseases.

4. Qu X, Li H, Hongyan Li, and Lingzhao Meng. "XBP1 regulates the transcription of HIF‐1a in BALB/c mice with chronic Rhinosinusitis without polyps." Analytical Cellular Pathology 2022.1 (2022): 3066456. https://doi.org/10.1155/2022/3066456

The article indicates that in chronic sinusitis (non-polypoid type), the expression of XBP1 is significantly elevated. Studies have revealed that XBP1 activates the Wnt/β-catenin signaling pathway by raising or lowering the oxygen-inducible factor HIF-1α, thereby driving nasal mucosal inflammation and tissue remodeling. Targeting XBP1 may offer a new direction for the treatment of this disease.

5. Salimi, Azam, et al. "XBP1 promotes NRASG12D pre‐B acute lymphoblastic leukaemia through IL‐7 receptor signalling and provides a therapeutic vulnerability for oncogenic RAS." Journal of Cellular and Molecular Medicine 27.21 (2023): 3363-3377. https://doi.org/10.1111/jcmm.17904

The article indicates that in RAS mutant precursor B-cell leukemia, XBP1 is a key downstream factor of IL-7 receptor signaling and maintains the survival and growth of cancer cells by regulating JAK1/STAT5. Targeting XBP1 not only induces apoptosis of cancer cells but also can be combined with the PI3K/mTOR inhibitor BEZ235, providing a new strategy for the treatment of this type of leukemia.

Creative Biolabs: XBP1 Antibodies for Research

Creative Biolabs specializes in the production of high-quality XBP1 antibodies for research and industrial applications. Our portfolio includes monoclonal antibodies tailored for ELISA, Flow Cytometry, Western blot, immunohistochemistry, and other diagnostic methodologies.

• Custom XBP1 Antibody Development: Tailor-made solutions to meet specific research requirements.
• Bulk Production: Large-scale antibody manufacturing for industry partners.
• Technical Support: Expert consultation for protocol optimization and troubleshooting.
• Aliquoting Services: Conveniently sized aliquots for long-term storage and consistent experimental outcomes.

For more details on our XBP1 antibodies, custom preparations, or technical support, contact us at email.