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At least 19 recordsLinked to original sources

PubMed1995

Dynamin forms polymeric complexes in the presence of lipid vesicles. Characterization of chemically cross-linked dynamin molecules.

Dynamin is a GTP-binding protein that is involved in the release of coated endocytic vesicles from the plasma membrane. We have been characterizing the enzymatic properties of purified rat brain dynamin to better understand how GTP binding and hydrolysis relate to its proposed function. Previously, we have demonstrated that activation of dynamin GTPase results from positive cooperative associations between dynamin molecules as they are bound to a polymeric surface. Our present report has extended these studies and has examined the structural features of dynamin self-association. After treatment with the zero-length protein cross-linking reagent, 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide, dynamin in solution was found cross-linked into dimers. This homodimer likely reflects the native soluble state of the molecule. After binding to brain vesicles, dynamin was cross-linked into higher order oligomers of greater than 800 kDa. Dynamin, copurified on brain membranous organelles, also formed multimeric complexes when cross-linked suggesting dynamin exists in polymeric form in vivo. No cross-linked species other than homo-oligomers were observed, providing no evidence for close interactions between dynamin and membrane proteins. From experiments examining the effects of GTP, GDP, guanosine 5'-3-O-(thio)triphosphate, and 5'-guanylyl-beta,gamma-imidodiphosphate on cross-linking, we have determined that both dynamin membrane binding and self-association occur independently from the nucleotide-bound state of the enzyme. An 80-kDa dynamin fragment that is lacking its carboxyl-terminal domain is not cross-linked into higher order oligomers, suggesting that this domain is required for binding of dynamin to membranes and the subsequent enhancement of oligomerization. However, the dynamin fragment was found to form dimers indicating that this domain is not required for dynamin dimerization. Cross-linked dynamin was able to cooperatively bind microtubules, but did not exhibit GTPase activation. We propose that intramolecular cross-links in the dynamin monomer impart structural constraints that prevent the enhancement of GTP hydrolysis. We describe a model of the dynamin activation process to be considered in further investigations of the role for dynamin in endocytic vesicle formation.

Animals↗

PubMed1992

Interaction of dynamin with microtubules: its structure and GTPase activity investigated by using highly purified dynamin.

We purified a large amount of dynamin with high enzymatical activity from rat brain tissue by a new procedure. Dynamin 0.48 mg was obtained from 20 g of rat brain. The purity of dynamin was almost 98%. Dynamin plays a role of GTPase rather than ATPase. In the absence of microtubules, Michaelis constant (Km) and maximum velocity (Vmax) for dynamin GTPase were 370 microM and 0.25 min-1, respectively, and in their presence, both were significantly accelerated up to 25 microM and 5.5 min-1. On the other hand, the ATPase activity was very low in the absence of microtubules, and even in their presence, Km and Vmax for dynamin ATPase were 0.2 mM and 0.91 min-1. Despite slow GTPase turnover rate in the absence of microtubules, binding of GTP and its nonhydrolizing analogues was very fast, indicating that GTP binding step is not rate limiting. Dynamin did not cause a one-directional consistent microtubule sliding movement just like kinesin or dynein in the presence of 2 mM ATP or 2 mM GTP. We observed the molecular structure of dynamin with low-angle rotary shadowing technique and revealed that the dynamin molecule is globular in shape. Gel filtration assay revealed that these globules were the oligomers of 100-kDa dynamin polypeptide. Dynamin bound to microtubules with a 1:1 approximately 1.2 molar ratio in the absence of GTP. Quick-freeze deep-etch electron microscopy of the dynamin-microtubule complex showed that dynamin decorates the surface of microtubules helically, like a screw bolt, very orderly and tightly with 11.4 +/- 0.9 (SD)nm period. Contrary to the previous report, microtubules make bundles by the attachment of the dynamin helixes around each adjacent microtubule, and no cross-bridge formation was observed.

Amino Acid Sequence↗

PubMed1997

Ubiquitously expressed dynamin-II has a higher intrinsic GTPase activity and a greater propensity for self-assembly than neuronal dynamin-I.

To begin to understand mechanistic differences in endocytosis in neurons and nonneuronal cells, we have compared the biochemical properties of the ubiquitously expressed dynamin-II isoform with those of neuron-specific dynamin-I. Like dynamin-I, dynamin-II is specifically localized to and highly concentrated in coated pits on the plasma membrane and can assemble in vitro into rings and helical arrays. As expected, the two closely related isoforms share a similar mechanism for GTP hydrolysis: both are stimulated in vitro by self-assembly and by interaction with microtubules or the SH3 domain-containing protein, grb2. Deletion of the C-terminal proline/arginine-rich domain from either isoform abrogates self-assembly and assembly-dependent increases in GTP hydrolysis. However, dynamin-II exhibits a approximately threefold higher rate of intrinsic GTP hydrolysis and higher affinity for GTP than dynamin-I. Strikingly, the stimulated GTPase activity of dynamin-II can be >40-fold higher than dynamin-I, due principally to its greater propensity for self-assembly and the increased resistance of assembled dynamin-II to GTP-triggered disassembly. These results are consistent with the hypothesis that self-assembly is a major regulator of dynamin GTPase activity and that the intrinsic rate of GTP hydrolysis reflects a dynamic, GTP-dependent equilibrium of assembly and disassembly.

Adaptor Proteins, Signal Transducing↗

PubMed1998

Perturbation of dynamin II with an amphiphysin SH3 domain increases GLUT4 glucose transporters at the plasma membrane in 3T3-L1 adipocytes. Dynamin II participates in GLUT4 endocytosis.

The GLUT4 glucose transporter continuously recycles between the cell surface and an endosomal compartment in adipocytes. Insulin decreases the rate of GLUT4 endocytosis in addition to increasing its exocytosis. Endocytosis of the transporter is thought to occur at least in part via the clathrin-mediated endocytic system. The protein dynamin is involved in the final stages of clathrin-coated vesicle formation. Here we show that the dynamin II isoform is expressed in 3T3-L1 adipocytes and is present in isolated plasma membrane and low density microsomal fractions. Insulin reduced the levels of dynamin II associated with the plasma membrane by about half, raising the possibility that the hormone may reduce GLUT4 endocytosis by removing dynamin from the cell surface. A fusion protein containing the amphiphysin SH3 domain selectively bound dynamin II from 3T3-L1 adipocyte cell lysates. Microinjection of the fusion protein into these cells inhibited transferrin endocytosis and increased the levels of GLUT4 at the cell surface. Glutathione S-transferase alone, the SH3 domains of spectrin and Crk, and a mutated amphiphysin SH3 domain unable to bind dynamin II did not affect GLUT4 distribution. However, a peptide containing the dynamin II sequence that binds amphiphysin increased the surface presence of GLUT4. Moreover, in cells first treated with insulin to externalize GLUT4, the dynamin peptide, but not an unrelated control peptide, inhibited GLUT4 internalization upon insulin removal. These results suggest that interactions of dynamin II with amphiphysin may play an important role in GLUT4 endocytosis. We hypothesize that insulin may reduce GLUT4 endocytosis by regulating the function of dynamin II at the cell surface, as part of the mechanism to increase glucose uptake.

3T3 Cells↗

PubMed1994

Growth factor-induced binding of dynamin to signal transduction proteins involves sorting to distinct and separate proline-rich dynamin sequences.

Dynamin, a 100 kDa GTPase, is critical for endocytosis, synaptic transmission and neurogenesis. Endocytosis accompanies receptor processing and plays an essential role in attenuating receptor tyrosine kinase signal transduction. Dynamin has been demonstrated to be involved in the endocytic processing at the cell surface and may play a general role in coupling receptor activation to endocytosis. Src homology (SH) domain dependent protein-protein interactions are important to tyrosine kinase receptor signal transduction. The C-terminus of dynamin contains two clusters of SH3 domain binding proline motifs; these motifs may interact with known SH3 domain proteins during tyrosine kinase receptor activation. We demonstrate here that SH3 domain-containing signal transduction proteins, such as phospholipase C gamma-1 (PLC gamma-1), do indeed bind to dynamin in a growth factor inducible manner. The induction of PLC gamma-1 binding to dynamin occurs within minutes of the addition of platelet derived growth factor (PDGF) to cells. Binding of these signal transduction proteins to dynamin involves specific sorting to individual proline motif clusters and appears to be responsible for co-immunoprecipitation of tyrosine phosphorylated PDGF receptors with dynamin following PDGF stimulation of mammalian cells. The binding of dynamin to SH3 domain-containing proteins may therefore be important for formation of the protein complex required for the endocytic processing of activated tyrosine kinase receptors.

3T3 Cells↗

PubMed1996

Phosphorylation of dynamin by ERK2 inhibits the dynamin-microtubule interaction.

In the present study we show that purified bovine brain dynamin can be phosphorylated by MAP kinase, ERK2, with a stoichiometry of 1 mol phosphate/mol dynamin. The phosphorylated serine residue is located within the C-terminal 10 kDa of dynamin. Dynamin I phosphorylated by ERK2 can be specifically dephosphorylated by calcineurin but not by protein phosphatase 2A (PP2A). Phosphorylation of dynamin by ERK2 weakens the binding of dynamin to microtubules and inhibits dynamin's microtubule-activated GTPase activity. Stimulation of GTPase activity by either Grb2 or phospholipids was not affected by ERK2 phosphorylation, suggesting that the binding sites for Grb2 and phospholipids do not overlap with that for microtubules.

Binding Sites↗

PubMed1992

Analysis of dynamin isoforms in mammalian brain: dynamin-1 expression is spatially and temporally regulated during postnatal development.

In adult rat brain, the microtubule-associated protein dynamin is composed of a closely spaced polypeptide doublet of approximately 100 kDa. Using an antibody preparation that is monospecific for dynamin-1 (the higher molecular mass isoform) we examined the temporal and regional expression of dynamin-1 in developing rat brain. Analysis of whole rat brain homogenates established that prior to postnatal day 9, dynamin-1 was present only at very low levels and thereafter its expression steadily increased with adult levels being attained by postnatal day 23. In individual regions of the brain, dynamin-1 levels were highest in cortex, amygdala, and striatum, significantly lower in olfactory bulb, cerebellum, and midbrain, and lowest in brainstem. During postnatal development, each of the regions exhibited approximately the same time course of protein expression except for a slight lag in expression in olfactory bulb. The spatial and temporal patterns of expression of dynamin-1 correlate with the establishment and/or maintenance of mature neuronal structure and function rather than dendritic or axonal outgrowth.

Age Factors↗

PubMed1998

Redundant and distinct functions for dynamin-1 and dynamin-2 isoforms.

A role for dynamin in clathrin-mediated endocytosis is now well established. However, mammals express three closely related, tissue-specific dynamin isoforms, each with multiple splice variants. Thus, an important question is whether these isoforms and splice variants function in vesicle formation from distinct intracellular organelles. There are conflicting data as to a role for dynamin-2 in vesicle budding from the TGN. To resolve this issue, we compared the effects of overexpression of dominant-negative mutants of dynamin-1 (the neuronal isoform) and dynamin-2 (the ubiquitously expressed isoform) on endocytic and biosynthetic membrane trafficking in HeLa cells and polarized MDCK cells. Both dyn1(K44A) and dyn2(K44A) were potent inhibitors of receptor-mediated endocytosis; however neither mutant directly affected other membrane trafficking events, including transport mediated by four distinct classes of vesicles budding from the TGN. Dyn2(K44A) more potently inhibited receptor-mediated endocytosis than dyn1(K44A) in HeLa cells and at the basolateral surface of MDCK cells. In contrast, dyn1(K44A) more potently inhibited endocytosis at the apical surface of MDCK cells. The two dynamin isoforms have redundant functions in endocytic vesicle formation, but can be targeted to and function differentially at subdomains of the plasma membrane.

Adenoviridae↗

PubMed2002

Dynamin-dependent and dynamin-independent processes contribute to the regulation of single vesicle release kinetics and quantal size.

Accumulating evidence suggests that the kinetics of release from single secretory vesicles can be regulated and that quantal size can be modified during fast kiss-and-run fusion. Multiple pathways for vesicle retrieval have been identified involving clathrin and dynamin. It has been unclear whether dynamin could participate in a fast kiss-and-run process to reclose a transient fusion pore and thereby limit vesicle release. We have disrupted dynamin function in adrenal chromaffin cells by expression of the amphiphysin Src-homology domain 3 (SH3) or by application of guanosine 5'-[gamma-thio]triphosphate (GTP gamma S), and have monitored single vesicle release events, evoked by digitonin and Ca(2+), by using carbon-fiber amperometry. Under both conditions, there was an increase in mean quantal size accompanying an increase in the half-width of amperometric spikes and a slowing of the fall time. These data suggest the existence of a dynamin-dependent process that can terminate vesicle release under basal conditions. Protein kinase C activation changed release kinetics and decreased quantal size by shortening the release period. The effects of phorbol ester treatment were not prevented by expression of the amphiphysin SH3 domain or by GTP gamma S suggesting the existence of alternative dynamin-independent process underlying fast kiss-and-run exocytosis.

Animals↗

PubMed2003

Syntaphilin binds to dynamin-1 and inhibits dynamin-dependent endocytosis.

Syntaphilin is a brain-specific syntaxin-binding partner first characterized as an inhibitor of SNARE complex formation and neurotransmitter release. Here we show that syntaphilin also binds to dynamin-1 and through this interaction inhibits dynamin-mediated endocytosis. Immunoprecipitation studies from cross-linked rat synaptosomes demonstrate that an endogenous syntaphilin-dynamin-1 complex exists independently of dynamin-1 binding to amphiphysin. Functionally, syntaphilin expression inhibits transferrin internalization in COS-7 cells. These data reveal that syntaphilin is an inhibitor of both SNARE-based fusion and dynamin-mediated endocytosis.

Animals↗

PubMed1999

Chlamydia infection of epithelial cells expressing dynamin and Eps15 mutants: clathrin-independent entry into cells and dynamin-dependent productive growth.

Chlamydiae enter epithelial cells via a mechanism that still remains to be fully elucidated. In this study we investigated the pathway of entry of C. psittaci GPIC and C. trachomatis LGV/L2 into HeLa cells and demonstrated that it does not depend on clathrin coated vesicle formation. We used mutant cell lines defective in clathrin-mediated endocytosis due to overexpression of dominant negative mutants of either dynamin I or Eps15 proteins. When clathrin-dependent endocytosis was inhibited by overexpression of the dynK44A mutant of dynamin I (defective in GTPase activity), Chlamydia entry was not affected. However, in these cells there was a dramatic inhibition in the proliferation of Chlamydia and the growth of the chlamydia vacuole (inclusion). When clathrin-dependent endocytosis was inhibited by overexpression of an Eps15 dominant negative mutant, the entry and growth of Chlamydia was unaltered. These results indicate that the effect on the growth of Chlamydia in the dynK44A cells was not simply due to a deprivation of nutrients taken up by endocytosis. Instead, the dominant-negative mutant of dynamin most likely affects the vesicular traffic between the Chlamydia inclusion and intracellular membrane compartments. In addition, cytochalasin D inhibited Chlamydia entry by more than 90%, indicating that chlamydiae enter epithelial cells by an actin-dependent mechanism resembling phagocytosis. Finally, dynamin is apparently not involved in the formation of phagocytic vesicles containing Chlamydia.

Actins↗

PubMed1997

Subcellular distribution of GLUT4 in Chinese hamster ovary cells overexpressing mutant dynamin: evidence that dynamin is a regulatory GTPase in GLUT4 endocytosis.

We have investigated the subcellular distribution of GLUT4 by immunofluorescence microscopy after transfection with wild-type or mutant dynamin cDNA into Chinese hamster ovary cells expressing insulin receptor and GLUT4. In the basal state, GLUT4 was distributed exclusively within the cells in the cells overexpressing wild-type dynamin (CHOIR-GLUT4-WT) but was located at the cell surface in the cells overexpressing mutant dynamin (CHOIR-GLUT4-K44E). Insulin induced subcellular shift of GLUT4 to the cell surface in CHOIR-GLUT4-WT cells but had little effect in CHOIR-GLUT4-K44E cells. When insulin-stimulated cells were treated with wortmannin, GLUT4 was redistributed within the cells in CHOIR-GLUT4-WT cell, whereas it remained at the cell surface in CHOIR-GLUT4-K44E cell. These results suggest that dynamin is a regulatory GTPase in endocytosis of GLUT4.

Animals↗

PubMed2002

Sustained stimulation shifts the mechanism of endocytosis from dynamin-1-dependent rapid endocytosis to clathrin- and dynamin-2-mediated slow endocytosis in chromaffin cells.

Transient stimulation of secretion in calf chromaffin cells is invariably followed by rapid endocytosis (RE), a clathrin- and K(+)-independent process with a half time of several seconds. Here we show that when exocytosis is triggered in a more sustained manner, a much slower form of endocytosis (SE) replaces RE. SE is complete within 10 min and is abolished when anticlathrin antibodies are introduced into the cell or when intracellular K(+) is removed. RE, but not SE, is blocked by intracellular administration of antidynamin-1 antibodies; the inverse specificity was found for antidynamin-2 antibodies. Replacement of extracellular Ca(2+) by Ba(2+) or Sr(2+) completely blocked RE but had little effect on SE. Thus chromaffin cells exhibit two kinetically and mechanistically distinct forms of endocytosis that are coupled to different extents of exocytosis and are mediated by different isoforms of dynamin. We surmise that RE is associated with the transient fusion ("kiss-and-run") mechanism of transmitter release and is the prevalent means of vesicle recapture and recycling under normal physiological conditions, whereas the clathrin-based SE mechanism comes into play only at higher levels of stimulation and may be associated with complete fusion of vesicles with the plasma membrane.

Animals↗

PubMed2002

The proline-rich domain of dynamin-2 is responsible for dynamin-dependent in vitro potentiation of endothelial nitric-oxide synthase activity via selective effects on reductase domain function.

The GTPase dynamin-2 (dyn-2) binds and positively regulates the nitric oxide-generating enzyme, endothelial nitric-oxide synthase (eNOS) (Cao, S., Yao, Y., McCabe, T., Yao, Q., Katusic, Z., Sessa, W., and Shah, V. (2001) J. Biol. Chem. 276, 14249-14256). Here we demonstrate, using purified proteins, that this occurs through a selective influence of the dyn-2 proline-rich domain (dyn-2 PRD) on the eNOS reductase domain. In vitro studies demonstrate that dyn-2 PRD fused with glutathione S-transferase (GST) binds recombinant eNOS protein specifically and with binding kinetics comparable with that observed between dyn-2 full-length and eNOS. Additionally, GST-dyn-2 PRD binds the in vitro transcribed (35)S-eNOS reductase domain but not the (35)S-eNOS oxygenase domain. Furthermore GST-dyn-2 PRD binds a (35)S-labeled eNOS reductase domain fragment (amino acids 645-850) that partially overlaps with the FAD binding domain of eNOS. A recombinant form of the SH3-containing protein Fyn competes the binding of recombinant eNOS protein with dyn-2 PRD, thereby implicating the SH3-like region contained within this reductase domain fragment as the dyn-2 binding region. Mammalian two-hybrid screen corroborates these interactions in cells as well. Functional studies demonstrate that dyn-2 PRD selectively potentiates eNOS activity in a concentration-dependent manner in an order of magnitude similar to that observed with dyn-2 full-length and in a manner that requires calmodulin. Although dyn-2 PRD does not influence eNOS oxygenase domain function or ferricyanide reduction, it does potentiate the ability of recombinant eNOS to reduce cytochrome c, supporting an influence of dyn-2 PRD on electron transfer between FAD and FMN. (These data indicate that the binding domains of dyn-2 and eNOS reside within the dyn-2 PRD domain and the FAD binding region of the eNOS reductase domains, respectively, and that dyn-2 PRD is sufficient to mediate dyn-2-dependent potentiation of eNOS activity, at least in part, by potentiating electron transfer.)

Amino Acid Sequence↗

PubMed1994

Differential expression and regulation of multiple dynamins.

Dynamin is a GTP-, microtubule-, and phospholipid-binding protein that is expressed primarily in brain. In Drosophila, the shibire gene encodes a homologue of dynamin; mutations in this gene result in a defect in endocytosis, suggesting a function for dynamin in endocytic membrane traffic. In the present study we show that there are at least two distinct dynamin genes in mammals whose products are referred to as dynamins I and II. The two dynamins are similar to each other (79% identity) and are both equally homologous to the Drosophila shibire gene product (66% identity). The highest degree of identity between dynamins is observed in their N-terminal halves, whereas their C termini exhibit little homology. Transcripts of both dynamin genes are subject to at least two alternative splicing events, the first of which is identically found in both dynamins, whereas the second site of alternative splicing is different between the two types of dynamins. The first alternatively spliced sequence of the dynamins consists of an interior region that is present in two distinct but homologous forms in both dynamins, suggesting alternative use of exons in both genes at identical positions. The second site of alternative splicing results in the generation of different C termini in dynamin I and in the inclusion or exclusion of an interior four-amino acid sequence in dynamin II. The two dynamins exhibit remarkable differences in their tissue distribution and regulation. Dynamin I is almost exclusively expressed in the central nervous system. Conversely, dynamin II is expressed ubiquitously in all tissues tested. Previous studies revealed that the GTPase activity of dynamin I is regulated by phosphorylation by protein kinase C in nerve terminals. Expression of dynamins I and II by transfection in COS cells demonstrates that only dynamin I but not dynamin II is a substrate for protein kinase C. Our data suggest a specialization in the endocytic functions and the regulation of dynamins between neural and non-neural tissues in mammals.

Amino Acid Sequence↗

PubMed2002

Distribution of dynamins in testis and their possible relation to spermatogenesis.

Dynamin 2 and dynamin 3 are highly expressed in testis. However, their functions in the tissue remain unclear. Considering that dynamin 1, neuron-specific isoform of dynamin, plays a pivotal role in endocytosis, functions of dynamin 2 and dynamin 3 in testis must be essential. Cellular expression and subcellular localization of dynamin 2 and dynamin 3 in testis were investigated. Dynamin 2 and dynamin 3 were highly expressed in germ cells and Sertoli cells, constituents of seminiferous tubules. By immunofluorescence it was revealed that dynamin 2 colocalizes with clathrin both at the plasmamembrane and at Golgi in a cell line of Sertoli cells. Immunoreactivity for dynamin 3, on the other hand, appeared as finer puncta, which did not colocalize with clathrin, suggesting that these two dynamins have distinct functions in Sertoli cells. In the klotho deficient mouse testis, which demonstrates disorder in spermatogenesis, expression of dynamin 2 and dynamin 3 was drastically reduced indicating possible association of these proteins with spermatogenesis.

Animals↗

PubMed2000

Dynamin II regulates hormone secretion in neuroendocrine cells.

The dynamin family of GTP-binding proteins has been implicated as playing an important role in endocytosis. In Drosophila shibire, mutations of the single dynamin gene cause blockade of endocytosis and neurotransmitter release, manifest as temperature-sensitive neuromuscular paralysis. Mammals express three dynamin genes: the neural specific dynamin I, ubiquitous dynamin II, and predominantly testicular dynamin III. Mutations of dynamin I result in a blockade of synaptic vesicle recycling and receptor-mediated endocytosis. Here, we show that dynamin II plays a key role in controlling constitutive and regulated hormone secretion from mouse pituitary corticotrope (AtT20) cells. Dynamin II is preferentially localized to the Golgi apparatus where it interacts with G-protein betagamma subunit and regulates secretory vesicle release. The presence of dynamin II at the Golgi apparatus and its interaction with the betagamma subunit are mediated by the pleckstrin homology domain of the GTPase. Overexpression of the pleckstrin homology domain, or a dynamin II mutant lacking the C-terminal SH3-binding domain, induces translocation of endogenous dynamin II from the Golgi apparatus to the plasma membrane and transformation of dynamin II from activity in the secretory pathway to receptor-mediated endocytosis. Thus, dynamin II regulates secretory vesicle formation from the Golgi apparatus and hormone release from mammalian neuroendocrine cells.

Amino Acid Sequence↗

PubMed1996

Three dynamin-encoding genes are differentially expressed in developing rat brain.

Dynamin proteins are members of a recently described family of GTPases involved in receptor-mediated processes. To date, three different dynamin-encoding genes have been identified in mammalian tissues. Dynamin I is expressed only in neurons, whereas dynamin II is ubiquitously expressed. A third isoform, dynamin III, was originally isolated from a rat testis cDNA library and shown to be testis-specific. However, here we report the cloning and characterization of dynamin III from brain and lung, demonstrating a more extended pattern of expression for this isoform. In addition, we have investigated the temporal pattern of expression of these three genes during brain development. We find that both dynamin I and dynamin III mRNA levels are up-regulated during embryogenesis, whereas dynamin II mRNA levels remain unchanged. From these results, we conclude that dynamin III is not a testis-specific isoform and, furthermore, that rat brain expresses three different dynamin-encoding genes that are differentially regulated during development. Therefore, this large isoform diversity of dynamin proteins in brain predicts a significant complexity in the understanding of dynamin-based processes in this tissue.

Alternative Splicing↗