Cell Biology

Evaluation Summary:

This paper provides an attempt to understand the crosstalk between to islet cell types during beta cell regeneration following partial pancreatectomy. It combines lineage tracing, single cell sequencing and light microscopy to describe islet cell heterogeneity and interactions in the regenerating mouse pancreas. The concept of protective signaling resulting from the direct interactions between beta and delta cells is compelling and would be of interest to scientists in the field of endocrine pancreas development and regeneration. However, the conclusions derived from the sequencing data require additional experimental support.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

This study investigates how deficiency in the RNA splicing factor SON impairs centriole assembly, which may underlie ciliopathy-like phenotypes in humans with SON mutations and is thus of interest to both cell biologists and clinicians. Using RNA-sequencing analysis and advanced imaging techniques the authors discover a large number of known and new SON splicing targets and attempt to identify those crucial for SON knockdown defects. However, knockdown of a subset of targets did not fully recapitulate SON depletion phenotypes and only led to the relatively vague conclusion that the observed centriole assembly defects were caused by impaired protein trafficking around the centrosome.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

This paper will be of interest to the chromosome biology field and SMC researchers in particular. The study provides cell biological, biochemical, and structural modeling evidence that a new Nse5-like protein named SIMC1 is a paralog of SLF1, and that the two compete for SLF2-Smc5/6 binding. The authors also show that SIMC1 targets SMC5/6 to polyomavirus replication centers through its SUMO binding motifs (SIMs), supporting a role for SIMC1 in Smc5/6 recruitment for viral restriction.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

Burl and Rondini et al. elucidate the transcriptional profile of the stromal vascular fraction of murine brown adipose tissue in the context of thermogenic stimulation. The authors combined systems and reductionist approaches to show the reliance of mature brown adipocytes on adrenergic activation to indirectly stimulate progenitor proliferation and differentiation and the involvement of dendritic cells in this process. Overall, this is a timely and well-rounded work that will provide beneficial data for public use and further resolve the complexities underlying brown adipose physiology.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 and Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

Nicastro et al. uncover a new input for the central metabolic regulator TOR complex 1 (TORC1) , namely manganese (Mn) levels, in budding yeast and they show that this dependence on Mn is conserved in humans. TORC1 is a central coordinator of multiple inputs to guide cellular decisions of catabolism vs anabolism, and information on an additional way to modulate its activity will be highly influential in both basic cell biology as well as therapeutic research.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1

Evaluation Summary:

Mitochondria have their own DNA, which is much more likely to gain mutation (due to error-prone DNA polymerase). It is widely appreciated that there are quality control mechanisms such that functional mitochondria are passed from one generation to the next. The proposed mechanisms include a passive mechanism (generation of the bottleneck) as well as an active mechanism (selective removal of non-functional mitochondria), but the processes are not fully understood. This manuscript presents fascinating observations as to how C. elegans germline may remove mitochondria by creating bottlenecks as well as selectively removing non-functional mitochondria. Building upon the authors' previous finding that the C. elegans primordial germ cells (PGCs) shed much of cytoplasm during embryogenesis through 'cannibalism', they now describe that a bulk of mitochondria are removed from PGCs through this process.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 agreed to share their name with the authors.)

Evaluation Summary:

This study provides important new information regarding the functions and behavior of lung tissue-resident alveolar macrophages in the context of acute lung injury. New data regarding the impact of hypoxia via HIF-1 on biology of these critical cells are provided and importantly suggesting an impact on the outcome of lung injury.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

Pond et al. established a 2D patient-derived organoid screening platform to study tissue patterning and kinase pathway dynamics. They aim to understand how the spacing of different colonic cell types and their communication are regulated. They found that apoptosis induces Erk signaling waves that prime cell movement and are essential to maintain tissue patterning in the organoid monolayers. The work presented here is of importance to the field and provides insights into how Erk waves driven by apoptosis can help maintain gut homeostasis.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

This article introduces "DetecDiv", a high throughput, deep learning method to perform automated cell-division tracking in yeast. The performance of the method, estimated to be 100 times faster than manual annotation, overcomes current time processing limitations that are inherent to large single cell datasets. In particular, DetecDiv allows to automatically get quantitative measurements of replicative life span in yeast. The method is of broad interest for quantitative biology as it can be used to study yeast cells dynamics across their lifespan.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

Here, the authors performed a CRISPR/Cas9 loss of function screen in polarized human epithelial cells to identify novel regulators of epithelial polarization and polarized membrane trafficking. This study provides a powerful resource for future investigations to unravel the complexity and diversity of mechanisms underlying epithelial polarization and polarized cargo transport. Furthermore, this dataset may represent an essential contribution to investigating novel congenital diseases associated with these processes, e.g., microvillus inclusion disease and necrotizing enterocolitis. A few experiments are suggested to bolster the authors' conclusions regarding the roles of key hits.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #2 and Reviewer #3 agreed to share their names with the authors.)