Target Name: USP44
NCBI ID: G84101
Other Name(s): Ubiquitin specific peptidase 44, transcript variant 2 | USP44 variant 6 | UBP44_HUMAN | ubiquitin specific protease 44 | ubiquitin thiolesterase 44 | ubiquitin specific peptidase 44 | USP44 variant 2 | Ubiquitin specific peptidase 44, transcript variant 6 | Ubiquitin thiolesterase 44 | Ubiquitin specific peptidase 44, transcript variant 1 | Ubiquitin specific protease 44 | FLJ14528 | Ubiquitin thioesterase 44 | ubiquitin thioesterase 44 | Ubiquitin carboxyl-terminal hydrolase 44 | DKFZp434D0127 | Ubiquitin-specific-processing protease 44 | deubiquitinating enzyme 44 | USP44 variant 1 | Deubiquitinating enzyme 44 | ubiquitin-specific-processing protease 44

USP44: Regulation of Protein Degradation and Homeostasis

USP44, also known as Ubiquitin Specific Peptidase 44, is a protein that is expressed in nearly all cells and tissues, and plays a crucial role in the regulation of protein degradation. It is a member of the ubiquitin enzyme family, which consists of a group of proteins that remove a ubiquitin molecule from target proteins, thereby regulating their stability and localization. USP44 is specific for the protein Ubiquitin, which is a large and short protein that is derived from the amino acid Lysine.

USP44 is involved in the degradation of a wide variety of proteins, including cytoskeletal components, enzymes involved in cell signaling pathways, and proteins involved in the immune response. It is also involved in the regulation of microtubule dynamics and the organization of organelles within cells. USP44 is regulated by several different factors, including the concentration of Ubiquitin, the activity of other ubiquitin enzymes, and the levels of protein degradation that occur in the cell.

One of the key features of USP44 is its ability to interact with other proteins. It has multiple interaction sites, including a binding site for the protein tyrosine phosphatase (TIP) and a binding site for the protein responsible for the degradation of the protein Myosin. These interactions allow USP44 to regulate the activity of other proteins and to play a role in the organization and dynamics of cellular structures.

USP44 is also involved in the regulation of protein homeostasis. It helps to ensure that the concentration of Ubiquitin in the cell is kept at a stable level, which is essential for the proper functioning of many cellular processes. This is achieved through the regulation of the activity of the enzyme ACID, which is involved in the synthesis of Acetyl-CoA, a molecule that is involved in the citric acid cycle and is a precursor to many different molecules, including proteins.

In addition to its role in regulating protein degradation, USP44 is also involved in the regulation of protein synthesis. It is involved in the delivery of proteins to the endoplasmic reticulum (ER), where they can be processed and degraded. This is achieved through the Regulation of the activity of the enzyme Transmembrane proteases (TMPs), which are involved in the delivery of proteins across the ER membrane.

USP44 is also involved in the regulation of cellular signaling pathways. It is involved in the degradation of the protein p16INK4a, which is a negative regulator of the transcription factor NF-kappa-B. This is achieved through the regulation of the activity of the enzyme Transthyretin hydrolase (TTH), which is involved in the degradation of p16INK4a. TTH activity is regulated by the concentration of Ubiquitin, which is itself regulated by the activity of USP44.

USP44 is also involved in the regulation of microtubule dynamics. It is involved in the degradation of the protein tubulin, which is a key component of microtubules. This is achieved through the regulation of the activity of the enzyme TOR, which is involved in the regulation of microtubule dynamics.

In conclusion, USP44 is a protein that plays a crucial role in the regulation of protein degradation, synthesis, and homeostasis. Its activity is regulated by several different factors, including the concentration of Ubiquitin, the activity of other ubiquitin enzymes, and the levels of protein degradation that occur in the cell. USP44 is also involved in the regulation of cellular signaling pathways, microtubule dynamics, and the regulation of protein homeostasis. As a drug target or biomarker, USP44 may be a valuable target for the development of new therapeutic strategies for a variety of diseases.

Protein Name: Ubiquitin Specific Peptidase 44

Functions: Deubiquitinase that plays a key regulatory role in the spindle assembly checkpoint or mitotic checkpoint by preventing premature anaphase onset. Acts by specifically mediating deubiquitination of CDC20, a negative regulator of the anaphase promoting complex/cyclosome (APC/C) (PubMed:17443180). Deubiquitination of CDC20 leads to stabilize the MAD2L1-CDC20-APC/C ternary complex (also named mitotic checkpoint complex), thereby preventing premature activation of the APC/C (PubMed:17443180). Promotes association of MAD2L1 with CDC20 and reinforces the spindle assembly checkpoint (PubMed:17443180). Promotes also the deubiquitination of histone H2A and H2B (PubMed:23615962, PubMed:27880911). Recruited to RNF8/RNF168-ubiquitinated chromatin surrounding double stranded breaks (DSBs), promotes hydrolysis of such ubiquitin conjugates, thus negatively regulating protein recruitment to damaged chromatin (PubMed:23615962). Participates in nucleotide excision repair (NER) pathway by deubiquitinating DDB2 to prevent its premature degradation so it can remain on damaged chromatin (By similarity). Promotes FOXP3 stabilization through 'Lys-48'-linked deubiquitination leading to increased stability and increased regulatory T-cell lineage stability (PubMed:32644293). Plays also a positive role in innate immune response to DNA viruses by deubiquitinating STING1, selectively removing its 'Lys-48'-linked polyubiquitin chains and stabilizing it (PubMed:31968013)

More Common Targets

USP45 | USP46 | USP46-DT | USP47 | USP48 | USP49 | USP5 | USP50 | USP51 | USP53 | USP54 | USP6 | USP6NL | USP6NL intronic transcript 1 (non-protein coding), transcript variant 1 | USP7 | USP8 | USP8P1 | USP9X | USP9Y | USPL1 | UST | UTF1 | UTP11 | UTP14A | UTP14C | UTP15 | UTP18 | UTP20 | UTP23 | UTP25 | UTP3 | UTP4 | UTP6 | UTRN | UTS2 | UTS2B | UTS2R | UTY | UVRAG | UVSSA | UXS1 | UXT | UXT-AS1 | VAC14 | Vacuolar H+ ATPase | VAMP1 | VAMP2 | VAMP3 | VAMP4 | VAMP5 | VAMP7 | VAMP8 | VANGL1 | VANGL2 | VAPA | VAPB | VARS1 | VARS2 | Vascular endothelial growth factor receptor (VEGFR) | Vascular endothelial growth factors (VEGF) | VASH1 | VASH1-AS1 | VASH2 | VASN | Vasoactive intestinal polypeptide receptor (VIP-R) | Vasohibin | Vasopressin Receptor | Vasopressin V1 Receptor | VASP | VAT1 | VAT1L | VAV1 | VAV2 | VAV3 | VAV3-AS1 | VAX1 | VAX2 | VBP1 | VCAM1 | VCAN | VCL | VCP | VCPIP1 | VCPKMT | VCX | VCX2 | VCX3A | VCX3B | VCY | VCY1B | VDAC1 | VDAC1P2 | VDAC1P9 | VDAC2 | VDAC2P5 | VDAC3 | VDR | VEGFA | VEGFB | VEGFC