LDHB

What is LDHB protein?

LDHB (lactate dehydrogenase B) gene is a protein coding gene which situated on the short arm of chromosome 12 at locus 12p12. This gene encodes the B subunit of lactate dehydrogenase enzyme called LDHB, which catalyzes the interconversion of pyruvate and lactate with concomitant interconversion of NADH and NAD+ in a post-glycolysis process. Alternatively spliced transcript variants have been found for this gene. Recent studies have shown that a C-terminally extended isoform is produced by use of an alternative in-frame translation termination codon via a stop codon readthrough mechanism, and that this isoform is localized in the peroxisomes. This protein is consisted of 334 amino acids and is approximately 36.6 kDa.

What is the Function of LDHB protein?

Lactate dehydrogenase B (LDHB) plays an important role in cellular energy metabolism and lactic acid balance, and is involved in the glycolysis pathway, which can convert glucose into pyruvate and lactic acid. By converting lactic acid to pyruvate, LDHB can participate in the cell's oxidative phosphorylation process, producing more ATP energy for the cell to use. In addition, LDHB is also involved in the elimination and transport of lactic acid, maintaining the balance of lactic acid inside and outside the cell.

LDHB Related Signaling Pathway

LDHB is mainly involved in the glycolysis pathway and its function is to convert glucose into pyruvate and lactic acid. However, in addition to these metabolic functions, studies have shown that LDHB also plays an important role in multiple signaling pathways. LDHB can activate VEGF/VEGFR2 signaling to regulate tumor angiogenesis. LDHB also regulates the NFKB signaling pathway through the mitochondrial autophagy pathway.

Fig1. The "Goldilocks principle" in regulating glycolysis and differentiation. (Xuyong Chen, 2023)

LDHB Related Diseases

Mutations in the LDHB gene have been linked to a variety of diseases, including:

Lactate dehydrogenase B deficiency (LDHBD): This is a rare genetic disorder in which patients lack LDHB enzyme activity, resulting in elevated levels of lactic acid and pyruvate. Metabolic diseases: LDHB is involved in the process of glucose metabolism and energy production, and abnormal expression of LDHB is associated with type 2 diabetes, obesity and metabolic syndrome. Cardiovascular diseases: LDHB is upregulated in myocardial ischemia-reperfusion injury and may be involved in cardiac cell death and cardiac function restoration. At the same time, LDHB is highly expressed in a variety of tumors, including breast cancer, lung cancer, and colon cancer.

Bioapplications of LDHB

LDHB has also been studied as a potential therapeutic target for cancer treatment. Inhibition of LDHB activity has been shown to impair tumor growth in preclinical studies. Targeting LDHB may help to disrupt the metabolism of cancer cells and sensitize them to other therapies.

Case Study 1: Suxing Jin, 2023

Fig1. The expressions of LDHA and LDHB relative to α-tubulin in SKOV-3 cells after treatment with CDDP, MDP, DDP (0.6 μM containing 0.6‰ DMSO), and DCF (1.2 μM containing 0.1‰ DMSO), respectively, for 36h.

Case Study 2: Manos Vlasiou, 2023

Fig2. Effect of tucatinib on tetramer formation and activity of LDH-B. Equal amounts of LDH-B (5 ng) were incubated with increasing concentrations of either tucatinib for 30 min, followed by loading onto 10% native (non-reducing) polyacrylamide gels.

LDHB has several biochemical functions, for example, L-lactate dehydrogenase activity,NAD binding,identical protein binding. Some of the functions are cooperated with other proteins, some of the functions could acted by LDHB itself. We selected most functions LDHB had, and list some proteins which have the same functions with LDHB. You can find most of the proteins on our site.

LDHB has direct interactions with proteins and molecules. Those interactions were detected by several methods such as yeast two hybrid, co-IP, pull-down and so on. We selected proteins and molecules interacted with LDHB here. Most of them are supplied by our site. Hope this information will be useful for your research of LDHB.

LDHA;PEX5;VCAM1;LRRK2;TERF1;RAC3;YWHAZ;TBK1;LDHA;artM4