Plasma Membrane Compartmentalization in Yeast by Messenger RNA Transport and a Septin Diffusion Barrier

Takizawa, Peter A.; DeRisi, Joseph L.; Wilhelm, James E.; Vale, Ronald D.

doi:10.1126/science.290.5490.341

Cited by 403 publications

(369 citation statements)

References 21 publications

Supporting

Mentioning

351

Contrasting

Unclassified

Order By: Relevance

“…Therefore, it might be the defect of actin cable-based transport, which leads to the phenotype observed when AgBNI1 is deleted. It is known from several studies, that actin cables can serve as tracks for different cargos such as secretory vesicles (Johnston et al, 1991) and several organelles (Simon et al, 1995;Hill et al, 1996;Hoepfner et al, 2001;Rossanese et al, 2001) as well as mRNA (Bobola et al, 1996;Sil and Herskowitz, 1996;Takizawa et al, 2000). Using the AgSec4p fused to GFP, we were able to show that secretory vesicles use actin cables for accumulation at the hyphal tips.…”

Section: Agbni1p and The Actin Cytoskeletonmentioning

confidence: 57%

From Function to Shape: A Novel Role of a Formin in Morphogenesis of the FungusAshbya gossypii

Schmitz

Kaufmann

Köhli

et al. 2006

MBoC

View full text Add to dashboard Cite

Morphogenesis of filamentous ascomycetes includes continuously elongating hyphae, frequently emerging lateral branches, and, under certain circumstances, symmetrically dividing hyphal tips. We identified the formin AgBni1p of the model fungus Ashbya gossypii as an essential factor in these processes. AgBni1p is an essential protein apparently lacking functional overlaps with the two additional A. gossypii formins that are nonessential. Agbni1 null mutants fail to develop hyphae and instead expand to potato-shaped giant cells, which lack actin cables and thus tip-directed transport of secretory vesicles. Consistent with the essential role in hyphal development, AgBni1p locates to tips, but not to septa. The presence of a diaphanous autoregulatory domain (DAD) indicates that the activation of AgBni1p depends on Rho-type GTPases. Deletion of this domain, which should render AgBni1p constitutively active, completely changes the branching pattern of young hyphae. New axes of polarity are no longer established subapically (lateral branching) but by symmetric divisions of hyphal tips (tip splitting). In wild-type hyphae, tip splitting is induced much later and only at much higher elongation speed. When GTP-locked Rho-type GTPases were tested, only the young hyphae with mutated AgCdc42p split at their tips, similar to the DAD deletion mutant. Two-hybrid experiments confirmed that AgBni1p interacts with GTP-bound AgCdc42p. These data suggest a pathway for transforming one axis into two new axes of polar growth, in which an increased activation of AgBni1p by a pulse of activated AgCdc42p stimulates additional actin cable formation and tip-directed vesicle transport, thus enlarging and ultimately splitting the polarity site.

show abstract

Section: Agbni1p and The Actin Cytoskeletonmentioning

confidence: 57%

From Function to Shape: A Novel Role of a Formin in Morphogenesis of the FungusAshbya gossypii

Schmitz

Kaufmann

Köhli

et al. 2006

MBoC

View full text Add to dashboard Cite

show abstract

“…It has been reported that many mRNAs and RNA-binding proteins are localized to specific compartments, along with cytoskeletal elements, in a variety of eukaryotic cells (Jansen, 2001;Kloc et al, 2002). In S. cerevisiae, many mRNAs are localized to produce proteins in specific compartments such as the daughter cell or the mitochondria (Corral-Debrinski et al, 2000;Takizawa et al, 2000;Jansen, 2001;Kwon and Schnapp, 2001;Shepard et al, 2003). These observations suggest that individual mRNAs may be consistently transported to specific areas in the yeast cell.…”

Section: Discussionmentioning

confidence: 97%

Simultaneous yet Independent Regulation of Actin Cytoskeletal Organization and Translation Initiation by Glucose inSaccharomyces cerevisiae

Uesono

Ashe

Toh‐e

2004

MBoC

View full text Add to dashboard Cite

Acute glucose deprivation rapidly but transiently depolarizes the actin cytoskeleton and inhibits translation initiation in Saccharomyces cerevisiae. Neither rapid actin depolarization nor translation inhibition upon glucose removal occurs in a reg1 disruptant, which is defective in glucose repression, or in the tpk1 w mutant, which has weak cAPK activity. In the absence of additional glucose, recovery of either actin polarization or translation initiation relies upon respiration, the Snf1p protein kinase, and the transcription factors Msn2p and Msn4p. The readdition of glucose to glucose-starved cells causes a rapid recovery of actin polarization as well as translation initiation without respiration. These results indicate that the simultaneous regulation of actin polarization and translation initiation is divided into three reactions: 1) rapid shutdown depending on Reg1p and cAPK after glucose removal, 2) slow adaptation depending on Snf1p and Msn2p/4p in the absence of glucose, and 3) rapid recovery upon readdition of glucose. On glucose removal, translation initiation is rapidly inhibited in a rom2 disruptant, which is defective in rapid actin depolarization, whereas rapid actin depolarization occurs in a pop2/caf1 disruptant, which is defective in rapid inhibition of translation initiation. Thus, translation initiation and actin polarization seem to be simultaneously but independently regulated by glucose deprivation. INTRODUCTIONThe actin cytoskeleton provides the structural basis for cell polarity in the yeast Saccharomyces cerevisiae and is organized primarily into two morphologically distinct structures: cortical patches and cables (Botstein et al., 1997). Cortical patches are discrete cytoskeletal bodies at the plasma membrane, whereas actin cables are long bundles of actin filaments that are oriented along the mother-bud axis. Both structures are polarized during the budding phase of the cell cycle. During early G1 phase, cortical patches and cables are randomly distributed. As a bud emerges, cortical patches cluster at the growing tip and cables extend from the mother cell into the bud. Near the end of bud growth, the patches and cables redistribute randomly, disrupting the asymmetric distribution of the actin cytoskeleton. At the end of mitosis, patches accumulate in and cables reorient toward the mother-bud neck in connection with cytokinesis and septum formation (Botstein et al., 1997).The actin cytoskeleton is also regulated in response to environmental stimuli. Mating pheromone causes polarization of the actin cytoskeleton toward the tip of the mating projection via the Cdc42p GTPase (Read et al., 1992;Leberer et al., 1997). In contrast, stresses such as osmotic shock, heat shock, and glucose starvation depolarize the actin cytoskeleton in budded cells as shown in Figure 1A (Novick et al., 1989;Chowdhury et al., 1992;Delley and Hall, 1999). In particular, the depolarization by heat or osmotic stress is known to be a rapid and transient reaction. A recent report has indicated that the rapid depol...

show abstract

“…Considering the high similarity of the expression patterns of SEPT4, SEPT7, and SEPT12, it is highly likely that the SEPT4/7/12 complex not only constitutes the structural basis of the annulus but also serves as a diffusion barrier between the various subcellular compartments of mammalian spermatozoa [6,11,35,36]. As alterations in the expression of one septin can lead to altered expression of other septins [5], the concomitant use of multiple markers (SEPT4 + SEPT7 + SEPT12) may be superior to any single marker as a sperm-quality index.…”

Section: Discussionmentioning

confidence: 99%

The expression pattern of SEPT7 correlates with sperm morphology

Chao

Lin

Kuo

et al. 2010

J Assist Reprod Genet

View full text Add to dashboard Cite

Purpose To investigate the expression pattern of the SEPT7 protein during spermatogenesis and its potential role in sperm function. Methods We first investigated the expression pattern of SEPT7 during different steps of mouse spermiogenesis using an immunofluorescence assay (IFA). IFA was also applied to study the expression pattern of SEPT7 in human ejaculated spermatozoa. Nine fertile men with normal semen parameters were used as the control group, and 21 infertile men with asthenozoospermia were recruited as the patient group. We assessed the frequency of the SEPT7 signal in the various morphological subgroups. Results In humans, the frequency of a defective SEPT7 signal was significantly increased in men with asthenozoospermia. The absence of a SEPT7 signal was more prevalent in sperm containing morphological defects of various types. Conclusions The expression pattern of SEPT7 suggested that this protein may be involved in the regulation of subcellular-compartment formation during spermiogenesis in the mouse. The absence of a SEPT7 signal correlated with multiple sperm defects.

show abstract

Plasma Membrane Compartmentalization in Yeast by Messenger RNA Transport and a Septin Diffusion Barrier

Cited by 403 publications

References 21 publications

From Function to Shape: A Novel Role of a Formin in Morphogenesis of the FungusAshbya gossypii

From Function to Shape: A Novel Role of a Formin in Morphogenesis of the FungusAshbya gossypii

Simultaneous yet Independent Regulation of Actin Cytoskeletal Organization and Translation Initiation by Glucose inSaccharomyces cerevisiae

The expression pattern of SEPT7 correlates with sperm morphology

Contact Info

Product

Resources

About