Ask about this productRelated genes to: INPP5K antibody
- Gene:
- INPP5K NIH gene
- Name:
- inositol polyphosphate-5-phosphatase K
- Previous symbol:
- -
- Synonyms:
- SKIP
- Chromosome:
- 17p13.3
- Locus Type:
- gene with protein product
- Date approved:
- 2008-09-09
- Date modifiied:
- 2015-08-25
Related products to: INPP5K antibody
Related articles to: INPP5K antibody
- Congenital muscular dystrophies (CMDs) are a genetically heterogeneous group of disorders. Variants in the INPP5K gene, which encodes a phosphoinositide phosphatase, are a rare cause of CMD. The condition is commonly associated with muscle weakness, early-onset cataracts, and intellectual disability, and prior reports have primarily identified missense, frameshift, or deletion variants. We describe the first Chinese case of INPP5K-related muscular dystrophy in a 28-year-old male with a mild phenotype, notably lacking intellectual disability. His presentation included bilateral cataracts at age 5 and adolescent onset limb girdle weakness. Muscle magnetic resonance imaging (MRI) revealed a characteristic pattern of selective fatty infiltration, with severe involvement of gluteal and thigh muscles and striking sparing of the rectus femoris, sartorius, and gracilis. Genetic analysis identified compound heterozygous novel INPP5K variants: a missense c.274C>T, p.(Arg92Cys) and a synonymous c.261G>A, p.(Lys87=) change. Functional studies confirmed the synonymous variant causes aberrant splicing (exon 3 skipping), leading to a frameshift and premature termination p.(Leu52SerfsTer49). According to American College of Medical Genetics and Genomics guidelines, the c.274C>T and c.261G>A variants were classified as likely pathogenic and pathogenic, respectively. This first report of a Chinese patient with INPP5K-related muscular dystrophy broadens both the genetic and clinical spectrum of the disorder. We identify the first disease-causing synonymous variant (via aberrant splicing) and a novel hypomorphic missense variant p.(Arg92Cys), the combination of which explains the attenuated phenotype lacking intellectual disability. Our case highlights the critical role of RNA analysis in diagnosing non-canonical variants and confirms the universal diagnostic relevance of the characteristic muscle MRI pattern. - Source: PubMed
Publication date: 2026/07/17
Liu YueLiang Hui - Cervical cancer (CESC) is a major gynecological malignancy, and abnormalities in phosphoinositide metabolism (PPM) are closely linked to tumor progression. This study aimed to screen phosphoinositide metabolism-related genes (PPM-RGs) with prognostic value for CESC and explore their molecular mechanisms and clinical significance. - Source: PubMed
Publication date: 2026/07/09
Meng HuiTan LiChen YingWang DongmeiQi YongZhu Chuchao - Inositol polyphosphate 5-phosphatase K (INPP5K) is a phosphatidylinositol (3,4,5)-trisphosphate phosphatase that increases glucose uptake and regulates myogenesis in the skeletal muscle. To understand the mechanism of its species-specific inhibition, we determined the 1.9-Å resolution crystal structure of human INPP5K in complex with a selective inhibitor, CPD-1 (IC50 = 2.9 µM). The structure reveals that CPD-1 binds to a novel allosteric pocket, inducing a large conformational change in α-helix 3 that alters the active site and prevents substrate binding. This finding explains its unique, noncompetitive inhibitory mechanism. Crucially, while the inhibitor-binding residues are conserved, the key residue governing the allosteric transition is not conserved in mouse and rat INPP5K, which correlates with their insensitivity to CPD-1 (IC50 > 100 µM). Based on these structural insights, we identified the hamster as a pharmacologically relevant preclinical model (IC50 = 8.2 µM). These findings provide a structural basis for the rational design of next-generation INPP5K inhibitors and establish a suitable animal model for their evaluation. - Source: PubMed
Publication date: 2026/02/26
Nomura AkihiroYamaguchi KeishiKawano MotoakiHanada KazukiNishihata JunNoguchi MasatoAdachi Tsuyoshi - CD19 is a central regulator of B-cell biology, acting both as a lineage marker and a critical modulator of signaling thresholds that govern development, activation, and tolerance. Structurally, CD19 is a heavily glycosylated transmembrane protein whose cytoplasmic domain harbors multiple tyrosine motifs serving as docking sites for key signaling molecules, including PI3K. Its expression is tightly regulated by transcriptional, post-transcriptional, and post-translational mechanisms, as well as by interactions with CD21 and CD81 in surface complexes. Genetic studies in mice and humans demonstrate that CD19 acts as a molecular rheostat, with both deficiency and overexpression leading to profound immunological dysfunctions ranging from hypogammaglobulinemia to autoimmunity. Importantly, recent work has revealed an additional level of CD19 signaling regulation mediated by conformational control of the CD19 cytoplasmic domain. A basic CD19 cytoplasmic juxtamembrane region engages in ionic interactions with PtdIns(4,5)P2, thereby influencing CD19 activation state. Loss of the 5-phosphatase INPP5K increases PtdIns(4,5)P2 levels, leading to constitutive CD19 signaling, impaired B-cell development and hypogammaglobulinemia. This discovery underscores the role of lipid-protein interactions in restraining inappropriate CD19 activation. Clinically, CD19 has emerged as a validated therapeutic target, with CAR T cells, bispecific antibodies, and monoclonal antibodies achieving remarkable efficacy in B-cell malignancies and autoimmune disorders. Understanding the fine regulation of CD19 expression, structure, and signaling remains essential to optimize therapeutic strategies. - Source: PubMed
Publication date: 2025/09/26
Schurmans StéphaneMoës Bastien - Phosphoinositides are membrane-bound phospholipids that are derived from the reversible phosphorylation of phosphatidylinositol by the opposing actions of phosphoinositide kinases and phosphatases. Phosphoinositides are minor lipid constituents of cellular membranes; however, they assert a varied and profound influence on numerous biological processes both at the plasma membrane and on subcellular organelle membranes. Phosphoinositide phosphatases encompass multiple enzyme families that hydrolyze the phosphate group from the inositol ring of phosphoinositide species to modify signaling pathways that govern development and homeostasis. Genetic mutations that alter the function or expression of phosphoinositide phosphatases are causative of severe developmental syndromes or contribute to human diseases such as cancer, metabolic disorders and neuropathies. This review will focus on a select group of phosphoinositide phosphatase family members. Specifically, we will discuss the lipid and dual-specificity protein phosphatase PTEN, including the multiple regulatory mechanisms that define this enzyme as an established tumor suppressor. We will focus on recent discoveries that describe novel roles for phosphoinositide regulation on subcellular membranes by INPP5E and INPP5K, two members of the inositol polyphosphate 5-phosphatase family. Finally, the diverse biological and pathophysiological roles of the inositol polyphosphate 4-phosphatases, INPP4A and INPP4B, will be outlined. Collectively, these discussions will reveal the critical roles that phosphoinositide phosphatases play in both human development and for prevention of disease. - Source: PubMed
Publication date: 2025/06/19
Davies Elizabeth MJones Emily IOoms Lisa MGurung RajendraMcGrath Meagan JMitchell Christina A