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Asymmetric division triggers cell-specific gene expression through coupled capture and stabilization of a phosphatase.

ABSTRACT: Formation of a division septum near a randomly chosen pole during sporulation in Bacillus subtilis creates unequal sized daughter cells with dissimilar programs of gene expression. An unanswered question is how polar septation activates a transcription factor (σ(F)) selectively in the small cell. We present evidence that the upstream regulator of σ(F), the phosphatase SpoIIE, is compartmentalized in the small cell by transfer from the polar septum to the adjacent cell pole where SpoIIE is protected from proteolysis and activated. Polar recognition, protection from proteolysis, and stimulation of phosphatase activity are linked to oligomerization of SpoIIE. This mechanism for initiating cell-specific gene expression is independent of additional sporulation proteins; vegetative cells engineered to divide near a pole sequester SpoIIE and activate σ(F) in small cells. Thus, a simple model explains how SpoIIE responds to a stochastically-generated cue to activate σ(F) at the right time and in the right place.

SUBMITTER: Bradshaw N

PROVIDER: S-EPMC4714977 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Restriction on self-renewing asymmetric division is coupled to terminal asymmetric division in the Drosophila CNS.

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| S-EPMC7521697 | biostudies-literature

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Cell type-specific attenuation of brassinosteroid signaling precedes stomatal asymmetric cell division

Project description:In Arabidopsis thaliana, brassinosteroid (BR) signaling and stomatal development are connected through the SHAGGY/GSK3-like kinase BR INSENSITIVE2 (BIN2). BIN2 is a key negative regulator of BR signaling but it plays a dual role in stomatal development. BIN2 promotes or restricts stomatal asymmetric cell division (ACD) depending on its subcellular localization, which is regulated by the stomatal lineage-specific scaffold protein POLAR. BRs inactivate BIN2, but how they govern stomatal development remains unclear. Mapping the single-cell transcriptome of stomatal lineages after triggering BR signaling with either exogenous BRs or the specific BIN2 inhibitor, bikinin, revealed that the two modes of BR signaling activation generate spatiotemporally distinct transcriptional responses. We established that BIN2 is always sensitive to the inhibitor but, when in a complex with POLAR and its closest homolog POLAR-LIKE1, it becomes protected from BR-mediated inactivation. Subsequently, BR signaling in ACD precursors is attenuated, while it remains active in epidermal cells devoid of scaffolds and undergoing differentiation. Our study demonstrates how scaffold proteins contribute to cellular signal specificity of hormonal responses in plants.

2023-08-30 | GSE193451 | GEO

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2024-09-27 | GSE268878 | GEO

Islr regulates satellite cells asymmetric division through Sparc/p-ERK1/2 signaling pathway

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2023-08-16 | GSE210951 | GEO

Haspin regulates mouse embryonic stem cell developmental potencies through Wnt5a mediated asymmetric cell division

Project description:To investigate the function of Haspin in the mouse embryonic stem cell, we established Haspin knockout cell lines.

2023-08-30 | GSE220824 | GEO

Dystrophin expression in muscle stem cells regulates their polarity and asymmetric division.

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