Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Negative Regulator Molecules

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.

Cells Coordinate Growth and Proliferation

Cells Coordinate Growth and Proliferation

Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...

Molecular Factors Affecting Cell Division

Molecular Factors Affecting Cell Division

Several external and internal factors influence the initiation and inhibition of cell division. For instance, the death of nearby cells or the release of human growth hormone (hGH) promotes cell division. In contrast, lack of hGH or crowding of cells can inhibit cell division.
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...

Stringent Response in E. coli

Stringent Response in E. coli

Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...

Positive Regulator Molecules

Positive Regulator Molecules

Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.

Positive Regulator Molecules

Positive Regulator Molecules

To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

A genome-wide CRISPR screen defines host determinants of early <i>Brucella</i> infection in human macrophage-like cells.

Infection and immunity·2026

Same author

A genome-wide CRISPR screen defines host determinants of early <i>Brucella</i> infection in human macrophage-like cells.

bioRxiv : the preprint server for biology·2026

Same author

Polar growth factor PgfA regulates polar peptidoglycan synthesis as well as mycolate synthesis in <i>Mycobacterium smegmatis</i>.

bioRxiv : the preprint server for biology·2026

Same author

An N4-like <i>Caulobacter</i> phage requires host smooth lipopolysaccharide biosynthesis for infection.

Journal of bacteriology·2026

Same author

The <i>hiuABC</i> operon mediates xenosiderophore utilization in <i>Caulobacter crescentus</i>.

Journal of bacteriology·2026

Same author

The <i>in vitro</i> stimulatory activity of CwlM∼P on mycobacterial MurA depends on a charged predicted interface that is distal from the CwlM phosphorylation site.

Frontiers in microbiology·2025

Search research articles

Related Experiment Video

Updated: May 28, 2026

Synchronization of Caulobacter Crescentus for Investigation of the Bacterial Cell Cycle

Synchronization of Caulobacter Crescentus for Investigation of the Bacterial Cell Cycle

Published on: April 8, 2015

ppGpp and polyphosphate modulate cell cycle progression in Caulobacter crescentus.

Cara C Boutte¹, Jonathan T Henry, Sean Crosson

¹Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA.

Journal of Bacteriology

|October 25, 2011

Summary

Nutrient deprivation in Caulobacter crescentus favors swarmer cells by inhibiting their development into stalked cells. This process is regulated by ppGpp and polyphosphate (polyP), acting as cell-type-specific developmental signals.

More Related Videos

Using Microtiter Dish Radiolabeling for Multiple In Vivo Measurements Of Escherichia coli (p)ppGpp Followed by Thin Layer Chromatography

Using Microtiter Dish Radiolabeling for Multiple In Vivo Measurements Of Escherichia coli (p)ppGpp Followed by Thin Layer Chromatography

Published on: June 4, 2019

A Purification and In Vitro Activity Assay for a (p)ppGpp Synthetase from Clostridium difficile

A Purification and In Vitro Activity Assay for a (p)ppGpp Synthetase from Clostridium difficile

Published on: November 3, 2018

Related Experiment Videos

Last Updated: May 28, 2026

Synchronization of Caulobacter Crescentus for Investigation of the Bacterial Cell Cycle

Synchronization of Caulobacter Crescentus for Investigation of the Bacterial Cell Cycle

Published on: April 8, 2015

Using Microtiter Dish Radiolabeling for Multiple In Vivo Measurements Of Escherichia coli (p)ppGpp Followed by Thin Layer Chromatography

Using Microtiter Dish Radiolabeling for Multiple In Vivo Measurements Of Escherichia coli (p)ppGpp Followed by Thin Layer Chromatography

Published on: June 4, 2019

A Purification and In Vitro Activity Assay for a (p)ppGpp Synthetase from Clostridium difficile

A Purification and In Vitro Activity Assay for a (p)ppGpp Synthetase from Clostridium difficile

Published on: November 3, 2018

Area of Science:

Microbiology
Cell Biology
Developmental Biology

Background:

Caulobacter crescentus undergoes a cell cycle involving differentiation from motile swarmer cells to sessile stalked cells.
Nutrient availability influences this developmental transition, with deprivation favoring the swarmer state.

Purpose of the Study:

To identify molecular signals regulating the swarmer-to-stalked cell transition during nutrient deprivation in Caulobacter crescentus.
To elucidate the roles of ppGpp and polyphosphate (polyP) in this developmental switch.

Main Methods:

Comparative analysis of swarmer and stalked cell populations under nutrient-rich and nutrient-depleted conditions.
Genetic manipulation to assess the impact of ppGpp and polyP synthesis deficiencies on cell cycle progression.
Microscopy and molecular assays to track key cell cycle regulators like CtrA and DivJ.

Main Results:

ppGpp and polyP were identified as key inhibitors of the swarmer-to-stalked cell transition under nutrient deprivation.
Cells lacking ppGpp or polyP synthesis exhibited aberrant stalk formation and premature chromosome replication upon carbon depletion.
Swamer cells were found to produce higher levels of ppGpp compared to stalked cells during starvation.

Conclusions:

ppGpp and polyP act as crucial cell-type-specific regulators that prevent premature differentiation of swarmer cells into stalked cells when nutrients are scarce.
These molecules ensure the maintenance of the motile swarmer population under unfavorable growth conditions, optimizing survival strategies.