CLASP homologues in Drosophila, Xenopus, and yeast are required for proper spindle assembly; in mammals, CLASP1 and CLASP2 both contribute to proper spindle assembly and microtubule dynamics in anaphase.  Under this scheme, the shape and size of the mitotic spindle are a function of the biophysical properties of the cross-linking motor proteins. The cytological findings of spindle cell lipomas include a population of adipocytes, spindle cells, and collagen bundles. Spindle cell SCC is a biphasic tumor with both a conventional SCC component and a malignant spindle cell component mimicking a mesenchymal malignancy. Microtubules can grow 1,000 times as long as their widths. Surprisingly, Mms19 exerts its spindle regulatory function again through different activities. Spindle cell SCC often presents as an exophytic, polypoid or pedunculated mass. Spindle neurons are not the only cell type affected in AD, nor is AD neuron loss confined to the anterior cingulate cortex, but this region of the brain clearly is involved in attention, memory, emotionality, vocalization, and other functions, including visual self-recognition. Chromosomes also shorten in length, up to 10,000 fold in animal cells, in a process called condensation. The presence of squamous differentiation, dyskeratotic cells, and continuity with the epidermis may assist in making the diagnosis. Furthermore, reducing the function of mdf-2 and a Mad3-like gene called san-1 decreased the observed frequency of metaphase stage cells after microtubule destabilization, suggesting that a spindle checkpoint functions in the early embryo (Nystul et al., 2003). 4.  Such sliding forces may account not only for spindle pole separation early in mitosis, but also spindle elongation during late anaphase. Again, careful attention to the absence of circumscription and the presence of diffusely infiltrating growth should point one toward the correct diagnosis. The extremities, most often the hands and feet, are most commonly involved. The microtubule-associated protein Augmin acts in conjunction with γ-TURC to nucleate new microtubules off of existing microtubules.  CLIP-associated proteins like CLASP1 in humans have also been shown to localize to plus-ends and the outer kinetochore as well as to modulate the dynamics of kinetochore microtubules (Maiato 2003). It is referred to as the mitotic spindle during mitosis, a process that produces genetically identical daughter cells, or the meiotic spindle during meiosis, a process that produces gametes with half the number of chromosomes of the parent cell. Spindle cell lesions of the breast cover a wide spectrum of diseases ranging from reactive tumor-like lesions to high-grade malignant tumors. Both are solitary, painless, well-circumscribed, and slowly growing lesions that often arise in the subcutis or dermis of the upper back, shoulder, neck or anterior head and neck regions of middle-aged to older men. Genome Organization and Function in the Cell Nucleus. The spindle cell component may show various growth patterns. Spindle cell rhabdomyosarcoma is characterized by a recurrent neomorphic p.L122R mutation in MYOD1 that occurs in combination with PI3K pathway activation and promotes proliferation through MYC. As they extend across the cell, they search for the centromere of each chromosome. Once they bind a kinetochore, they are stabilized and their dynamics are reduced.  Although how CLIP170 recognizes plus-ends remains unclear, it has been shown that its homologues protect against catastrophe and promote rescue, suggesting a role for CLIP170 in stabilizing plus-ends and possibly mediating their direct attachment to kinetochores. Most spindled angiosarcomas show focal areas of typical angiosarcoma, characterized by more epithelioid cells forming primitive vascular channels. Muscle spindles stimulate reflexively a muscle contraction to prevent overstretching and muscle fiber damage, this is known as the stretch or myotatic reflex . LAWRENCE M. WEISS, in Modern Surgical Pathology (Second Edition), 2009. The spindle apparatus cells centers on a cell structure called the ?. This represents etiologically and genetically a diverse group of melanomas. The diagnosis can be difficult when only a spindle cell component is present.  Additional microtubule destabilizing proteins include Op18/stathmin and katanin which have roles in remodeling the mitotic spindle as well as promoting chromosome segregation during anaphase. Depends on the skin, soft tissues, and S100.62 is tapered at both ends cells [ 7 and. Tend to divide along their long axis according to the growing tips of microtubules to chromosomes at kinetochores! 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