HICE1 antibody

Aurora-A phosphorylates the Hice1 Augmin protein complex at the N-terminal serine/threonine group to modulate microtubule-binding activity during spindle assembly.

Correct assembly of mitotic spindles requires Hice1, a spindle-associated protein. Hice1 has direct microtubule-binding activity at its N-terminal region and contributes to intramembranous microtubule nucleation as a subunit of the Augmin complex. However, it remains unexplored whether the microtubule-binding activity of Hice1 is modulated by mitotic regulators. Here, we found that Aurora-A kinase, one of the major mitotic kinases, specifically binds to and phosphorylates Hice1. We identified four serine/threonine groups on Hice1 that can be phosphorylated by Aurora-A in vitro. Among the four groups, the Ser/Thr-17-21 group was the most important for bipolar spindle assembly, while other phosphorus-deficient point mutants had little effect on spindle assembly. Immunostaining with phosphorylated Ser-19/20 antibody revealed that Hice1 phosphorylation is mainly localized to the spindle poles during prophase to telophase, but gradually decreases after anaphase. Consistently, the phospholipid 17-21E mutant decreased microtubule-binding activity in vitro and decreased spindle localization in vivo. Furthermore, expression of the 17-21E mutant decreased the binding of Fam29a, a component of Augmin, to spindles. On the other hand, expression of the phosphorous-deficient 17-21A mutant allowed nucleation within the spindle but delayed early mitotic spindle pole separation and mitotic progression over time. Taken together, these results indicate that Aurora-A modulates the microtubule-binding activity of Hice1 in a spatiotemporal manner for proper assembly of the bipolar spindle.

Regulation of microtubule-based microtubule nucleation by a mammalian Polo-like kinase 1.

The formation of the bipolar spindle is essential for the precise segregation of mitotic chromosomes during cell division. A growing body of evidence indicates that, in addition to chromatin (MT) and nucleolar micronucleus-dependent nucleation, MT-based nucleation plays an important role in the proper formation of the bipolar spindle in many eukaryotic organisms. Although the recently discovered Augmin complex plays an important role in this event, how Augmin is organized is unknown. Here we provide evidence that mammalian polo-like kinase 1 (Plk1) is translated into mitotic spindles and enhances MT-based nucleation through direct regulation of Augmin. Mechanistically, we show that Cdc2-dependent phosphorylation of the γ-tubulin loop (γ-TuRC) recruitment protein, Nedd1/GCP-WD, at the previously uncharacterized S460 residue induces the Nedd1-Plk1 interaction. This step seemed critical to allow Plk1 to phosphorylate the Hice1 subunit of the Augmin complex to promote Augmin-MT interaction and nuclear MT-based MT from within the spindle. Loss-of-function of Nedd1 S460 or Plk1-dependent phosphorylation of Hice1 impaired Augmin-MT interaction and γ-tubulin recruitment to spindles, resulting in inappropriate bipolar spindle formation ultimately leading to mitotic arrest and apoptosis. Thus, through the formation of the Nedd1-Plk1 complex and subsequent Augmin phosphorylation, Plk1 regulates spindle-based MT nucleation to achieve normal bipolar spindle formation and mitotic progression.

Hec1 contributes to the growth of centriolar mitotic microtubules for proper spindle assembly through interaction with Hice1.

Previous studies have indicated that Hec1 is a conserved kinetochore component important for mitotic control in part by directly binding to mitotic spindle kinetochore fibers and recruiting the spindle assembly checkpoint proteins Mad1 and Mad2. Hec1 has also been reported to localize to centrosomes, but its function remains to be elucidated. Here, we show that Hec1 specifically colocalizes with Hice1, a previously characterized microtubule-associated protein, in the spindle pole region during mitosis. Furthermore, the C-terminal region of Hec1 binds directly to the coiled-coil domain 1 of Hice1. Hice1 depletion by small interfering RNA (siRNA) reduced Hec1 levels in the cell, preferentially in the centrosomes and adjacent to the spindle axis. De novo microtubule nucleation of mitotic centrosomes could be observed in cells treated with siRNA Hec1 or Hice1. Consistently, neutralization of Hec1 or Hice1 by specific antibodies impairs microtubule formation from purified mitotic centrosomes in vitro.


Hice1, a novel microtubule-associated protein required to maintain spindle integrity and chromosome stability in human cells.

Spindle integrity is critical for efficient mitotic progression and accurate chromosome segregation. Spindle dysregulation often leads to structural and functional aberrations, ultimately promoting segregation errors and aneuploidy, a hallmark of most human cancers. Here we report the characterization of a previously identified human sarcoma antigen (a gene located at 19p13.11), Hice1, an evolutionarily non-conserved 46 kDa coiled protein. Hice1 shows a distinct visceral localization and is associated with interphase centers and mitotic spindles, preferentially at the periphery of the spindle pole. Hice1 depletion by RNA interference resulted in abnormal and unstable spindle formations, delayed cleavage at prophase I and metaphase, and elevated aneuploidy. In contrast, loss of Hice1 had minor effects on centrosome duplication in interphase. We also found that both Hice1 and full-length Hice1-N1, which consisted of 149 amino acids in the N-terminal region, but not the mutant lacking the N-terminal region, showed activities to assemble and stabilize proximal microtubules. physiological approach. Consistently, Hice1 overexpression resulted in microtubule bundles in cells resistant to cocodazole or cold treatment-induced depolymerization. These results demonstrate that Hice1 is a novel microtubule-associated protein important for maintaining spindle integrity and chromosomal stability, in part due to its ability to bind, assemble, and stabilize microtubules.

HICE1 antibody

22053 SAB 100ul 479 EUR

HICE1 antibody

22053-100ul SAB 100ul 468 EUR

HICE1 antibody

70R-12549 Fitzgerald 100 ul 550 EUR

HICE1 antibody

MBS9414555-01mL MyBiosource 0.1mL 420 EUR

HICE1 antibody

MBS9414555-5x01mL MyBiosource 5x0.1mL 1740 EUR

HICE1 antibody

MBS835783-01mL MyBiosource 0.1mL 1070 EUR

HICE1 antibody

MBS835783-5x01mL MyBiosource 5x0.1mL 4655 EUR

Rabbit polyclonal HICE1 PS70 antibody

TA319224 Origene Technologies GmbH 100 µg Ask for price

HICE1 Recombinant Protein (Human)

RP014656 ABM 100 ug Ask for price

Rabbit polyclonal antibody to HICE1 (HAUS augmin-like complex, subunit 8)

TA307936 Origene Technologies GmbH 100 µl Ask for price

HICE1 ORF Vector (Human) (pORF)

ORF004886 ABM 1.0 ug DNA 114 EUR

HICE1 Protein Vector (Human) (pPM-C-HA)

PV019543 ABM 500 ng 394.8 EUR

HICE1 Protein Vector (Human) (pPB-C-His)

PV019541 ABM 500 ng 394.8 EUR

HICE1 Protein Vector (Human) (pPB-N-His)

PV019542 ABM 500 ng 394.8 EUR

HICE1 Protein Vector (Human) (pPM-C-His)

PV019544 ABM 500 ng 394.8 EUR

Structural Comparison and Drug Screening of Spike Proteins for Ten Variants of SARS-CoV-2

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) has developed several variants with stronger infection and immune evasion than the parent strain, including Alpha, Beta, Gamma, Delta, Epsilon, Kappa, Iota, Lambda and 21 H. La amino acid mutants are enriched in the spike protein of SARS-CoV-2, which plays an important role in cellular infection. However, the effect of these mutations on protein structure and function is unclear. Understanding the pathophysiology and epidemiological characteristics of SARS-CoV-2 variants requires knowledge of skeletal protein structures. Here, we obtained the raised protein structures of ten globally endemic strains of SARS-CoV-2 using AlphaFold2. Structural similarity-based clustering analysis revealed the unique features of primarily SARS-CoV-2 epidemic delta variants, indicating that structural assemblies may more accurately reflect current epidemic features than sequence-based ones. proteins. Analysis of the binding affinities of ACE2-RBD, anti-NTD and anti-RBD in the different variants revealed that the recognition of antibodies against S1 NTD and RBD was decreased in the variants, especially in the delta variant compared to the strain original. , which can induce immunity. evasion of SARS-CoV-2 variants. Furthermore, through virtual screening of the ZINC database against the predicted high-resolution structure of the Delta Spike protein and experimental validation, we identified multiple compounds targeting the NTD S1s and RBDs, which may contribute to the development of anti- Clinical SARS-CoV-2. . drugs. Our findings provided an essential foundation for future in vitro and in vivo research that may accelerate the development of potential treatments for SARS-CoV-2 variants.

Nonbactericidal cathelicidin provides protective efficacy against bacterial infection by promoting phagocytic flow

The bactericidal role of cathelicidins against bacterial infections has been extensively studied. However, the antibacterial properties and mechanism of action of nonbactericidal cathelicidins are rarely known. Here, a new natural cathelicidin (PopuCATH) from the tree frog (Polypedates puerensis) did not show direct antibacterial activity in vitro. Interestingly, intraperitoneal injection of PopuCATH prior to bacterial inoculation significantly reduced bacterial load in tree frogs and mice, and reduced the inflammatory response induced by bacterial inoculation in mice. PopuCATH pretreatment also increased survival rates of septic mice induced by a lethal dose of bacterial inoculation or cecal ligation and drilling (CLP). Intraperitoneal injection of PopuCATH significantly increased leukocyte entry in both frogs and miceacrophages by activating the mitogen-activated protein kinases p38/ERK (MAPK) and p65 NF-κB. PopuCATH significantly improved neutrophil phagocytosis by enhancing the release of extracellular neutrophil traps (NETs). Furthermore, PopuCATH has shown few side effects both in vitro and in vivo. Together, PopuCATH acts as a host-based immune defense regulator that provides protective efficacy against bacterial infection without direct antimicrobial effects. Our findings reveal a non-bactericidal cathelicidin that possesses a unique antibacterial effect and highlights the potential of PopuCATH in preventing bacterial infections.

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