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Seven kinds of intermediate filament networks in the cytoplasm of polarized cells: structure and function.

Iwatsuki H, Suda M - Acta Histochem Cytochem (2010)

Bottom Line: However, little information exists on the structure of the IF networks performing these functions.We have clarified the existence of seven kinds of IF networks in the cytoplasm of diverse polarized cells: an apex network just under the terminal web, a peripheral network lying just beneath the cell membrane, a granule-associated network surrounding a mass of secretory granules, a Golgi-associated network surrounding the Golgi apparatus, a radial network locating from the perinuclear region to the specific area of the cell membrane, a juxtanuclear network surrounding the nucleus, and an entire cytoplasmic network.In this review, we describe these seven kinds of IF networks and discuss their biological roles.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomy, Kawasaki Medical School, Matsushima 577, Kurashiki 701-0192, Japan. iwatsuki@med.kawasaki-m.ac.jp

ABSTRACT
Intermediate filaments (IFs) are involved in many important physiological functions, such as the distribution of organelles, signal transduction, cell polarity and gene regulation. However, little information exists on the structure of the IF networks performing these functions. We have clarified the existence of seven kinds of IF networks in the cytoplasm of diverse polarized cells: an apex network just under the terminal web, a peripheral network lying just beneath the cell membrane, a granule-associated network surrounding a mass of secretory granules, a Golgi-associated network surrounding the Golgi apparatus, a radial network locating from the perinuclear region to the specific area of the cell membrane, a juxtanuclear network surrounding the nucleus, and an entire cytoplasmic network. In this review, we describe these seven kinds of IF networks and discuss their biological roles.

No MeSH data available.


Related in: MedlinePlus

Schematic representation of the embryonic and postnatal neurogenesis in the developing and adult rabbit spinal ganglia. Ovoid cells, which originate from the vimentin-positive neural crest, differentiate into NF-positive pseudounipolar neurons, GFAP/vimentin-positive glial cells (satellite cells and Schwann cells), and keratin-positive polymorphic cells during prenatal life. The polymorphic cells, which express keratin 8, keratin 14, nestin, NF-L and GFAP, differentiate into pseudounipolar neurons and glial cells after birth. When the polymorphic cells differentiate into neurons, the immature neurons transiently express these five kinds of IF proteins as a Golgi-associated filament network (GAN).
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Figure 11: Schematic representation of the embryonic and postnatal neurogenesis in the developing and adult rabbit spinal ganglia. Ovoid cells, which originate from the vimentin-positive neural crest, differentiate into NF-positive pseudounipolar neurons, GFAP/vimentin-positive glial cells (satellite cells and Schwann cells), and keratin-positive polymorphic cells during prenatal life. The polymorphic cells, which express keratin 8, keratin 14, nestin, NF-L and GFAP, differentiate into pseudounipolar neurons and glial cells after birth. When the polymorphic cells differentiate into neurons, the immature neurons transiently express these five kinds of IF proteins as a Golgi-associated filament network (GAN).

Mentions: As shown in Figure 11, we recognized two kinds of cell lineages in the neurogenesis in the developing and adult rabbit spinal ganglion by studying the changes in the composition of this network [66]. Spinal ganglia arise from the neural crest [111], and migrating neural crest cells exclusively express vimentin [9]. As shown in Figure 12, these neural crest cells differentiate into nestin-positive ovoid cells with an eccentric nucleus through the spindle-shaped cells co-expressing vimentin and nestin in the rudiments of the spinal ganglia. Some ovoid cells co-express nestin with either NF-L or GFAP. Nestin has been utilized as a histochemical marker for identifying neural stem cells of the central nervous system [18, 43, 117, 147, 150]. NF-L is expressed in embryonic neurons [54, 121], and GFAP is expressed in satellite cells [81, 126] and Schwann cells [30, 69]. In addition, these nestin-positive ovoid cells cannot be observed in newborn and adult ganglia. Therefore, they seem to be an embryonic neural stem cell of the spinal ganglion. In the rudiments of the spinal ganglia, a few keratin-positive polymorphic cells also exist among the ovoid cells. These polymorphic cells co-express five kinds of IF proteins, namely, keratin 8, keratin 14, nestin, NF-L, and GFAP. Since cells co-expressing vimentin and keratin cannot be detected in the rudiments, it seems that the keratin-positive polymorphic cell is not derived directly from the neural crest, but from the nestin-positive ovoid cells. These keratin-positive polymorphic cells can also be detected in newborn and adult ganglia (Fig. 13). The possibility that the keratin-positive polymorphic cell is a postnatal neural stem cell of the spinal ganglion can be considered for the following three reasons. First, keratin has been detected not only in undifferentiated neuronal cells [74, 89], but also in dedifferentiated tumor cells of the nervous system [19, 50, 73, 103, 133, 148]. Therefore, keratin, in addition to nestin, can also be utilized as a valuable histochemical marker for neuronal stem cells. Second, the polymorphic cells have the ability to differentiate into both neurons and glial cells, since they contain NF-L and GFAP in addition to keratin and nestin. Third, a few neurons in the adult ganglion also express these five kinds of IF proteins as a Golgi-associated network. However, neurons expressing these five kinds of proteins cannot be detected in either the embryonic or newborn spinal ganglia. Therefore, it is conjectured that the polymorphic cells expressing the five kinds of IF proteins differentiate into neuronsafter birth, and that immature neurons transiently express the five kinds of IF proteins as a Golgi-associated network when polymorphic cells differentiate into the neurons.


Seven kinds of intermediate filament networks in the cytoplasm of polarized cells: structure and function.

Iwatsuki H, Suda M - Acta Histochem Cytochem (2010)

Schematic representation of the embryonic and postnatal neurogenesis in the developing and adult rabbit spinal ganglia. Ovoid cells, which originate from the vimentin-positive neural crest, differentiate into NF-positive pseudounipolar neurons, GFAP/vimentin-positive glial cells (satellite cells and Schwann cells), and keratin-positive polymorphic cells during prenatal life. The polymorphic cells, which express keratin 8, keratin 14, nestin, NF-L and GFAP, differentiate into pseudounipolar neurons and glial cells after birth. When the polymorphic cells differentiate into neurons, the immature neurons transiently express these five kinds of IF proteins as a Golgi-associated filament network (GAN).
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2875862&req=5

Figure 11: Schematic representation of the embryonic and postnatal neurogenesis in the developing and adult rabbit spinal ganglia. Ovoid cells, which originate from the vimentin-positive neural crest, differentiate into NF-positive pseudounipolar neurons, GFAP/vimentin-positive glial cells (satellite cells and Schwann cells), and keratin-positive polymorphic cells during prenatal life. The polymorphic cells, which express keratin 8, keratin 14, nestin, NF-L and GFAP, differentiate into pseudounipolar neurons and glial cells after birth. When the polymorphic cells differentiate into neurons, the immature neurons transiently express these five kinds of IF proteins as a Golgi-associated filament network (GAN).
Mentions: As shown in Figure 11, we recognized two kinds of cell lineages in the neurogenesis in the developing and adult rabbit spinal ganglion by studying the changes in the composition of this network [66]. Spinal ganglia arise from the neural crest [111], and migrating neural crest cells exclusively express vimentin [9]. As shown in Figure 12, these neural crest cells differentiate into nestin-positive ovoid cells with an eccentric nucleus through the spindle-shaped cells co-expressing vimentin and nestin in the rudiments of the spinal ganglia. Some ovoid cells co-express nestin with either NF-L or GFAP. Nestin has been utilized as a histochemical marker for identifying neural stem cells of the central nervous system [18, 43, 117, 147, 150]. NF-L is expressed in embryonic neurons [54, 121], and GFAP is expressed in satellite cells [81, 126] and Schwann cells [30, 69]. In addition, these nestin-positive ovoid cells cannot be observed in newborn and adult ganglia. Therefore, they seem to be an embryonic neural stem cell of the spinal ganglion. In the rudiments of the spinal ganglia, a few keratin-positive polymorphic cells also exist among the ovoid cells. These polymorphic cells co-express five kinds of IF proteins, namely, keratin 8, keratin 14, nestin, NF-L, and GFAP. Since cells co-expressing vimentin and keratin cannot be detected in the rudiments, it seems that the keratin-positive polymorphic cell is not derived directly from the neural crest, but from the nestin-positive ovoid cells. These keratin-positive polymorphic cells can also be detected in newborn and adult ganglia (Fig. 13). The possibility that the keratin-positive polymorphic cell is a postnatal neural stem cell of the spinal ganglion can be considered for the following three reasons. First, keratin has been detected not only in undifferentiated neuronal cells [74, 89], but also in dedifferentiated tumor cells of the nervous system [19, 50, 73, 103, 133, 148]. Therefore, keratin, in addition to nestin, can also be utilized as a valuable histochemical marker for neuronal stem cells. Second, the polymorphic cells have the ability to differentiate into both neurons and glial cells, since they contain NF-L and GFAP in addition to keratin and nestin. Third, a few neurons in the adult ganglion also express these five kinds of IF proteins as a Golgi-associated network. However, neurons expressing these five kinds of proteins cannot be detected in either the embryonic or newborn spinal ganglia. Therefore, it is conjectured that the polymorphic cells expressing the five kinds of IF proteins differentiate into neuronsafter birth, and that immature neurons transiently express the five kinds of IF proteins as a Golgi-associated network when polymorphic cells differentiate into the neurons.

Bottom Line: However, little information exists on the structure of the IF networks performing these functions.We have clarified the existence of seven kinds of IF networks in the cytoplasm of diverse polarized cells: an apex network just under the terminal web, a peripheral network lying just beneath the cell membrane, a granule-associated network surrounding a mass of secretory granules, a Golgi-associated network surrounding the Golgi apparatus, a radial network locating from the perinuclear region to the specific area of the cell membrane, a juxtanuclear network surrounding the nucleus, and an entire cytoplasmic network.In this review, we describe these seven kinds of IF networks and discuss their biological roles.

View Article: PubMed Central - PubMed

Affiliation: Department of Anatomy, Kawasaki Medical School, Matsushima 577, Kurashiki 701-0192, Japan. iwatsuki@med.kawasaki-m.ac.jp

ABSTRACT
Intermediate filaments (IFs) are involved in many important physiological functions, such as the distribution of organelles, signal transduction, cell polarity and gene regulation. However, little information exists on the structure of the IF networks performing these functions. We have clarified the existence of seven kinds of IF networks in the cytoplasm of diverse polarized cells: an apex network just under the terminal web, a peripheral network lying just beneath the cell membrane, a granule-associated network surrounding a mass of secretory granules, a Golgi-associated network surrounding the Golgi apparatus, a radial network locating from the perinuclear region to the specific area of the cell membrane, a juxtanuclear network surrounding the nucleus, and an entire cytoplasmic network. In this review, we describe these seven kinds of IF networks and discuss their biological roles.

No MeSH data available.


Related in: MedlinePlus