ASS1 Antibodies

Structure of ASS1

The protein encoded by the ASS1 gene has a molecular weight of approximately 46.7 kDa and is composed of 412 amino acids. It shows high conservation across different species.

ASS1 exists in a homotrimeric form, with each subunit containing three domains: the N-terminal nucleotide-binding domain, the central hinge domain, and the C-terminal domain. The active center is located at the interface of the subunits and is composed of multiple conserved residues. The enzyme activity depends on the participation of Mg2+ ions and catalyzes the formation of arginine succinate from citrulline and aspartic acid. This enzyme plays a rate-limiting role in the urea cycle and its expression is regulated by transcriptional levels and post-translational modifications.

Fig. 1 Suggested model for the requirement of ASS1 in the p53-response to DNA damage.¹

The key structural features of ASS1:

• Homodimeric structure, with each subunit consisting of three domains
• The active center is located at the interface of the subunits and contains multiple conserved catalytic residues
• Mg²⁺ ions participate in the catalytic reaction and stabilize the transition state conformation
• The C-terminal domain mediates the assembly of the dimer and maintains the stability of the enzyme activity

Functions of ASS1

The core function of ASS1 is to catalyze the formation of argininosuccinate from citrulline and aspartic acid, which is a rate-limiting enzyme in the urea cycle. However, it also plays a role in various physiological and pathological processes, including arginine synthesis, nitric oxide regulation, and tumor metabolic remodeling.

In tumor cells, ASS1 is often silenced due to promoter methylation. Its absence leads to the redirection of aspartic acid to pyrimidine synthesis, promoting the proliferation of cancer cells. This metabolic reprogramming provides a theoretical basis for arginine deprivation therapy.

Applications of ASS1 and ASS1 Antibody in Literature

1. Lim, Lisha Qiu Jin, et al. "ASS1 metabolically contributes to the nuclear and cytosolic p53-mediated DNA damage response." Nature metabolism 6.7 (2024): 1294-1309. https://doi.org/10.1038/s42255-024-01060-5

The research has found that ASS1 is part of the p53 network. After DNA damage, it inhibits nucleotide synthesis and regulates chromatin remodeling to arrest the cell cycle for DNA repair. The absence of ASS1 leads to DNA damage and accelerated cell cycle, promoting tumor mutations and adaptation.

2. Luo, Wensong, et al. "ASS1 inhibits triple-negative breast cancer by regulating PHGDH stability and de novo serine synthesis." Cell death & disease 15.5 (2024): 319. https://doi.org/10.1038/s41419-024-06672-z

The research has found that ASS1 can bind to PHGDH and promote its degradation, thereby inhibiting serine synthesis and exerting an anti-cancer effect. Knocking out PHGDH can reverse the anti-cancer effect of ASS1. The absence of ASS1 will enhance the proliferation ability of cells in an environment lacking serine.

3. Panda, Prashanta Kumar, et al. "BCL-XL Protects ASS1-Deficient Cancers from Arginine Starvation–Induced Apoptosis." Clinical Cancer Research 31.7 (2025): 1333-1345. https://doi.org/10.1158/1078-0432.CCR-24-2548

The research has found that cancer cells lacking ASS1 depend on arginine for survival. ADI-PEG20 can inhibit the cell cycle, but its efficacy is limited as BCL-XL combines with BAX/BAK to block apoptosis. Combining with BCL-XL inhibitors can remove the blockade and synergistically induce apoptosis, providing a basis for clinical combination therapy.

4. Qian, Xiangjun, et al. "ZFPL1 Promotes Colorectal Cancer Progression by Stabilizing ASS1 to Drive the Urea Cycle and M2 Macrophage‐Mediated Metastatic Colonization." Advanced Science 12.46 (2025): e05291. https://doi.org/10.1002/advs.202505291

The study found that ZFPL1 is highly expressed in colorectal cancer. It activates the urea cycle by binding to ASS1 and inhibiting its degradation, thereby promoting tumor progression. The absence of ZFPL1 can reshape the immune microenvironment. Compound Sal B can block the binding of ZFPL1 and ASS1, and synergistically enhance the efficacy of immunotherapy.

5. Khare, Sanika, et al. "ASS1 and ASL suppress growth in clear cell renal cell carcinoma via altered nitrogen metabolism." Cancer & Metabolism 9.1 (2021): 40. https://doi.org/10.1186/s40170-021-00271-8

The study found that in renal clear cell carcinoma, the expression of urea cycle enzymes ASS1 and ASL was downregulated. Their absence could enable aspartate to be redirected to pyrimidine synthesis, thereby promoting cancer cell proliferation. Restoring the expression of both enzymes could inhibit tumor growth by depleting aspartate and regulating nitric oxide synthesis.

Creative Biolabs: ASS1 Antibodies for Research

Creative Biolabs specializes in the production of high-quality ASS1 antibodies for research and industrial applications. Our portfolio includes monoclonal and polyclonal antibodies tailored for ELISA, Flow Cytometry, Western blot, immunohistochemistry, and other diagnostic methodologies.

• Custom ASS1 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 ASS1 antibodies, custom preparations, or technical support, contact us at email.