Reassessing the Role of Hox Genes during Vertebrate Development and Evolution

Flavor characterization of pork cuts in Chalu black pigs using multi-omics analysis

The study investigated the flavor variations in four different fresh pork cuts (longissimus thoracis, LT; trapezius muscle, TM; hamstring muscle, HM; Pork Belly, PB) from Chalu black pigs (ten castrated boars) using multi-omics techniques. The research also explored the influence of muscle fiber type on the flavor profiles of these cuts. Results from quantitative real-time PCR (qRT-PCR) indicated significant differences in muscle fiber type across the four pork cuts in various anatomical locations. Each cut exhibited distinctive volatile organic compounds (VOCs) profiles, with HM displaying a sweet and fruity green flavor, LT showcasing a fatty and nutty taste, PB presenting a fresh, citrusy, and green flavor, and TM offering a floral and bitter note. Variations in fatty acid carbon number and saturation were observed among the cuts, with HM, LT, and PB being rich in fatty acids with C16-18, C19-21, and 3 double bonds, respectively. The metabolites specific to each cut were found to play key roles in different metabolic pathways, such as protein-related pathways for HM, arginine biosynthesis for LT, lysine biosynthesis for PB, and D-arginine and D-ornithine metabolism for TM. Differentially expressed genes (DEGs) were associated with amino acid metabolism for HM, glycolysis/gluconeogenesis for LT, and cellular aromatic compound organization for PB. Notably, HM and PB displayed unique flavor characteristics, while TM exhibited relatively neutral features. The study also identified correlations among VOCs, muscle fiber type, lipids, metabolites, and gene patterns specific to each cut, highlighting the complex interplay of factors influencing pork flavor.

lncRNA WAC-AS1 promotes the progression of gastric cancer through miR-204-5p/HOXC8 axis

LncRNAs affect tumorigenesis, and although the genesis, regulation and physiological mechanism of lncRNAs in gastric cancer (GC) have been reported, the research of lncRNAs still have a lot of value. Through comprehensive bioinformatics analysis, we screened the candidate lncRNA WAC-AS1(WAC-AS1). We analyzed WAC-AS1 expression in GC related tissues and cells using qRT-PCR. WAC-AS1's impact on GC growth and metastasis was investigated. LncRNA WC-AS-miR-204-5p-HOXC8 interaction was established through dual-luciferase reporter, FISH, RIP and RNA pull-down assay. We observed substantial upregulation in WAC-AS1 expression in cells and tissues of GC. WAC-AS1 through miR-204-5p/HOXC8 axis promoted GC proliferation, invasion, and migration. WAC-AS1 plays a cancer-promoting role for promoting the progression of GC.

Heritability in the Rhesus Macaque (Macaca mulatta) Vertebral Column

The vertebral column plays a central role in primate locomotion and positional behavior. Understanding its evolution, therefore, has the potential to clarify evolutionary processes that have occurred in the primate lineage as well as the specific behaviors of extinct primates. However, to understand primate vertebral anatomy, it is important to determine how much of this anatomy is heritable and how much develops as a response to environmental factors during life. We estimated heritability for vertebral counts as well as typical cervical, thoracic, and lumbar elements from 210 individuals from the pedigreed Cayo Santiago Macaca mulatta skeletal collection. We found moderate heritability of vertebral counts (h2 = 0.216-0.326), but with strong heritability of the type of variation (e.g., a tendency to meristic or homeotic change) in the vertebral count (h2 = 0.599), suggesting a possible explanation for high variability in vertebral numbers among the hominoids in particular. The moderate heritability of vertebral count also suggests that vertebral count is an unsuitable metric for estimating the ancestral state for some taxa. We found strong heritability in the morphology of cervical and upper lumbar zygapophyseal facets (h2 = 0.548-0.550) and the thoracic spinous processes (h2 = 0.609-0.761), including high heritability of the spinous process angle in the upper thoracic and upper lumbar elements (h2 = 0.649-0.752). We suggest these are related to maintaining stability in the cervical and lumbar regions, and reducing motion in the thoracic region, respectively. We propose that spinous processes may contain greater phylogenetic information, whereas transverse processes may contain greater information of function 'in life'. We also found important size effects, suggesting that size is the most heritable component of overall form and largely responsible for intertrait differences. This suggests that it is inappropriate to indiscriminately remove size effects from morphological comparisons.

Genome-wide association study reveals the underlying regulatory mechanisms of red blood traits in Anadara granosa

BACKGROUND

Anadara granosa, commonly known as the blood clam, exhibits the unusual characteristic of having red blood among invertebrates. There is significant individual variation in blood color intensity among blood clams; individuals with vibrant red blood are deemed healthier and exhibit stronger stress resistance. However, the molecular basis underlying these red blood traits (RBTs) remains poorly understood.

RESULTS

In this study, we performed genome-wide association studies (GWAS) in a population of 300 A. granosa individuals, focusing on RBTs as measured by hemoglobin concentration (HC), total hemocyte count (THC), and heme concentration (HEME). Our analysis identified 18 single nucleotide polymorphisms (SNPs) correlated with RBTs, subsequently selected 117 candidate genes within a 100 kb flanking region of these SNPs, potentially involved in the RBTs of A. granosa. Moreover, we discovered two haplotype blocks specifically associated with THC and HEME. Further analysis revealed eight genes (Septin7, Hox5, Cbfa2t3, Avpr1b, Hhex, Eif2ak3, Glrk, and Rpl35a) that significantly influence RBTs. Notably, a heterozygous A/T mutation in the 3'UTR of Cbfa2t3 was found to promote blood cell proliferation. These genes suggest that the hematopoietic function plays a significant role in the variability of RBTs in A. granosa.

CONCLUSIONS

Our findings reveal a conservation of the regulatory mechanisms of RBTs between blood clams and vertebrates. The results not only provide a scientific basis for selective breeding in blood clams, but also offer deeper insights into the evolutionary mechanisms of RBTs in invertebrates.

Chromosome-level dairy goat genome reveals the regulatory landscape of lactation

Goat milk is rich in various nutrients that are beneficial for human health. However, the genomic evolution and genetic basis underlying the nutritional value and unique flavor formation in dairy goats remain poorly understood. In the present study, we generate a chromosome-level genome assembly for dairy goats comprising 2.63 Gb with a contig N50 of 43 Mb and a scaffold N50 of 101 Mb. Genome quality comparisons revealed that the dairy goat genome has higher integrity and continuity than the published goat and sheep genomes. The identification of genes under positive selection in dairy goats highlights potential candidates to explain their high milk production. Comparative genomic analysis elucidates the adaptive evolutionary mechanisms of dairy goats such as strong disease resistance, broad adaptability, and unique milk flavor. Moreover, we demonstrate the conservation of the lactation gene network and identify new potential regulators associated with lipid metabolism. Additionally, we establish the regulatory landscape of lactation for the first time in dairy goats, revealing its unique gene regulatory characteristics. Hence, our study not only provides the first chromosome-level reference genome for dairy goat, but also offers potential research directions for dairy production and genetic improvement.

HOXB2 promotes cisplatin resistance by upregulating lncRNA DANCR in ovarian cancer

Ovarian cancer (OV) is a highly fatal malignant disease that commonly manifests at an advanced stage. Drug resistance, particularly platinum resistance, is a leading cause of treatment failure because first-line systemic chemotherapy primarily relies on platinum-based regimens. By analyzing the gene expression levels in the Cancer Genome Atlas database, Genotype-Tissue Expression database, and Gene Expression Omnibus datasets, we discerned that HOXB2 was highly expressed in OV and was associated with poor prognosis and cisplatin resistance. Immunohistochemistry and loss-of-function experiments on HOXB2 were conducted to explore its role in OV. We observed that suppressing HOXB2 could impair the growth and cisplatin resistance of OV in vivo and in vitro. Mechanical investigation and experimental validation based on RNA-Seq revealed that HOXB2 regulated ATP-binding cassette transporter members and the ERK signaling pathway. We further demonstrated that HOXB2 modulated the expression of long non-coding RNA DANCR, a differentiation antagonizing non-protein coding RNA, and thus influenced its downstream effectors ABCA1, ABCG1, and ERK signaling to boost drug resistance and cancer proliferation. These results verified that high expression of HOXB2 correlated with platinum resistance and poor prognosis of OV. Therefore, targeting HOXB2 may be a promising strategy for OV therapy.

The pathogenic mechanism of syndactyly type V identified in a Hoxd13Q50R knock-in mice

Syndactyly type V (SDTY5) is an autosomal dominant extremity malformation characterized by fusion of the fourth and fifth metacarpals. In the previous publication, we first identified a heterozygous missense mutation Q50R in homeobox domain (HD) of HOXD13 in a large Chinese family with SDTY5. In order to substantiate the pathogenicity of the variant and elucidate the underlying pathogenic mechanism causing limb malformation, transcription-activator-like effector nucleases (TALEN) was employed to generate a Hoxd13Q50R mutant mouse. The mutant mice exhibited obvious limb malformations including slight brachydactyly and partial syndactyly between digits 2-4 in the heterozygotes, and severe syndactyly, brachydactyly and polydactyly in homozygotes. Focusing on BMP2 and SHH/GREM1/AER-FGF epithelial mesenchymal (e-m) feedback, a crucial signal pathway for limb development, we found the ectopically expressed Shh, Grem1 and Fgf8 and down-regulated Bmp2 in the embryonic limb bud at E10.5 to E12.5. A transcriptome sequencing analysis was conducted on limb buds (LBs) at E11.5, revealing 31 genes that exhibited notable disparities in mRNA level between the Hoxd13Q50R homozygotes and the wild-type. These genes are known to be involved in various processes such as limb development, cell proliferation, migration, and apoptosis. Our findings indicate that the ectopic expression of Shh and Fgf8, in conjunction with the down-regulation of Bmp2, results in a failure of patterning along both the anterior-posterior and proximal-distal axes, as well as a decrease in interdigital programmed cell death (PCD). This cascade ultimately leads to the development of syndactyly and brachydactyly in heterozygous mice, and severe limb malformations in homozygous mice. These findings suggest that abnormal expression of SHH, FGF8, and BMP2 induced by HOXD13Q50R may be responsible for the manifestation of human SDTY5.

Enriched Single-Nucleus RNA-Sequencing Reveals Unique Attributes of Distal Convoluted Tubule Cells

SIGNIFICANCE STATEMENT

High-resolution single-nucleus RNA-sequencing data indicate a clear separation between primary sites of calcium and magnesium handling within distal convoluted tubule (DCT). Both DCT1 and DCT2 express Slc12a3, but these subsegments serve distinctive functions, with more abundant magnesium-handling genes along DCT1 and more calcium-handling genes along DCT2. The data also provide insight into the plasticity of the distal nephron-collecting duct junction, formed from cells of separate embryonic origins. By focusing/changing gradients of gene expression, the DCT can morph into different physiological cell states on demand.

BACKGROUND

The distal convoluted tubule (DCT) comprises two subsegments, DCT1 and DCT2, with different functional and molecular characteristics. The functional and molecular distinction between these segments, however, has been controversial.

METHODS

To understand the heterogeneity within the DCT population with better clarity, we enriched for DCT nuclei by using a mouse line combining "Isolation of Nuclei Tagged in specific Cell Types" and sodium chloride cotransporter-driven inducible Cre recombinase. We sorted the fluorescently labeled DCT nuclei using Fluorescence-Activated Nucleus Sorting and performed single-nucleus transcriptomics.

RESULTS

Among 25,183 DCT cells, 75% were from DCT1 and 25% were from DCT2. In addition, there was a small population (<1%) enriched in proliferation-related genes, such as Top2a , Cenpp , and Mki67 . Although both DCT1 and DCT2 expressed sodium chloride cotransporter, magnesium transport genes were predominantly expressed along DCT1, whereas calcium, electrogenic sodium, and potassium transport genes were more abundant along DCT2. The transition between these two segments was gradual, with a transitional zone in which DCT1 and DCT2 cells were interspersed. The expression of the homeobox genes by DCT cells suggests that they develop along different trajectories.

CONCLUSIONS

Transcriptomic analysis of an enriched rare cell population using a genetically targeted approach clarifies the function and classification of distal cells. The DCT segment is short, can be separated into two subsegments that serve distinct functions, and is speculated to derive from different origins during development.

GDF11: An emerging therapeutic target for liver diseases and fibrosis

Growth differentiation factor 11 (GDF11), also known as bone morphogenetic protein 11 (BMP11), has been identified as a key player in various biological processes, including embryonic development, aging, metabolic disorders and cancers. GDF11 has also emerged as a critical component in liver development, injury and fibrosis. However, the effects of GDF11 on liver physiology and pathology have been a subject of debate among researchers due to conflicting reported outcomes. While some studies suggest that GDF11 has anti-aging properties, others have documented its senescence-inducing effects. Similarly, while GDF11 has been implicated in exacerbating liver injury, it has also been shown to have the potential to reduce liver fibrosis. In this narrative review, we present a comprehensive report of recent evidence elucidating the diverse roles of GDF11 in liver development, hepatic injury, regeneration and associated diseases such as non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), liver fibrosis and hepatocellular carcinoma. We also explore the therapeutic potential of GDF11 in managing various liver pathologies.

Whole-Genome Scanning for Selection Signatures Reveals Candidate Genes Associated with Growth and Tail Length in Sheep

Compared to Chinese indigenous sheep, Western sheep have rapid growth rate, larger physique, and higher meat yield. These excellent Western sheep were introduced into China for crossbreeding to expedite the enhancement of production performance and mutton quality in local breeds. Here, we investigated population genetic structure and genome-wide selection signatures among the Chinese indigenous sheep and the introduced sheep based on whole-genome resequencing data. The PCA, N-J tree and ADMIXTURE results showed significant genetic difference between Chinese indigenous sheep and introduced sheep. The nucleotide diversity (π) and linkage disequilibrium (LD) decay results indicated that the genomic diversity of introduced breeds were lower. Then, Fst & π ratio, XP-EHH, and de-correlated composite of multiple signals (DCMS) methods were used to detect the selection signals. The results showed that we identified important candidate genes related to growth rate and body size in the introduced breeds. Selected genes with stronger selection signatures are associated with growth rate (CRADD), embryonic development (BVES, LIN28B, and WNT11), body size (HMGA2, MSRB3, and PTCH1), muscle development and fat metabolism (MSTN, PDE3A, LGALS12, GGPS1, and SAR1B), wool color (ASIP), and hair development (KRT71, KRT74, and IRF2BP2). Thus, these genes have the potential to serve as candidate genes for enhancing the growth traits of Chinese indigenous sheep. We also identified tail-length trait-related candidate genes (HOXB13, LIN28A, PAX3, and VEGFA) in Chinese long-tailed breeds. Among these genes, HOXB13 is the main candidate gene for sheep tail length phenotype. LIN28A, PAX3, and VEGFA are related to embryonic development and angiogenesis, so these genes may be candidate genes for sheep tail type traits. This study will serve as a foundation for further genetic improvement of Chinese indigenous sheep and as a reference for studies related to growth and development of sheep.

Sea cucumbers: an emerging system in evo-devo

A challenge for evolutionary developmental (evo-devo) biology is to expand the breadth of research organisms used to investigate how animal diversity has evolved through changes in embryonic development. New experimental systems should couple a relevant phylogenetic position with available molecular tools and genomic resources. As a phylum of the sister group to chordates, echinoderms extensively contributed to our knowledge of embryonic patterning, organ development and cell-type evolution. Echinoderms display a variety of larval forms with diverse shapes, making them a suitable group to compare the evolution of embryonic developmental strategies. However, because of the laboratory accessibility and the already available techniques, most studies focus on sea urchins and sea stars mainly. As a comparative approach, the field would benefit from including information on other members of this group, like the sea cucumbers (holothuroids), for which little is known on the molecular basis of their development. Here, we review the spawning and culture methods, the available morphological and molecular information, and the current state of genomic and transcriptomic resources on sea cucumbers. With the goal of making this system accessible to the broader community, we discuss how sea cucumber embryos and larvae can be a powerful system to address the open questions in evo-devo, including understanding the origins of bilaterian structures.

Advancements in Genetic Marker Exploration for Livestock Vertebral Traits with a Focus on China

In livestock breeding, the number of vertebrae has gained significant attention due to its impact on carcass quality and quantity. Variations in vertebral traits have been observed across different animal species and breeds, with a strong correlation to growth and meat production. Furthermore, vertebral traits are classified as quantitative characteristics. Molecular marker techniques, such as marker-assisted selection (MAS), have emerged as efficient tools to identify genetic markers associated with vertebral traits. In the current review, we highlight some key potential genes and their polymorphisms that play pivotal roles in controlling vertebral traits (development, length, and number) in various livestock species, including pigs, donkeys, and sheep. Specific genetic variants within these genes have been linked to vertebral development, number, and length, offering valuable insights into the genetic mechanisms governing vertebral traits. This knowledge has significant implications for selective breeding strategies to enhance structural characteristics and meat quantity and quality in livestock, ultimately improving the efficiency and quality of the animal husbandry industry.

Emergence of a left-right symmetric body plan in vertebrate embryos

External bilateral symmetry is a prevalent feature in vertebrates, which emerges during early embryonic development. To begin with, vertebrate embryos are largely radially symmetric before transitioning to bilaterally symmetry, after which, morphogenesis of various bilateral tissues (e.g somites, otic vesicle, limb bud), and structures (e.g palate, jaw) ensue. While a significant amount of work has probed the mechanisms behind symmetry breaking in the left-right axis leading to asymmetric positioning of internal organs, little is known about how bilateral tissues emerge at the same time with the same shape and size and at the same position on the two sides of the embryo. By discussing emergence of symmetry in many bilateral tissues and structures across vertebrate model systems, we highlight that understanding symmetry establishment is largely an open field, which will provide deep insights into fundamental problems in developmental biology for decades to come.

Sequential gene expression analysis of myelodysplastic syndrome transformation identifies HOXB3 and HOXB7 as the novel targets for mesenchymal cells in disease

BACKGROUND

Myelodysplastic syndrome (MDS) is known to arise through the pathogenic bone marrow mesenchymal stem cells (MSC) by interacting with hematopoietic stem cells (HSC). However, due to the strong heterogeneity of MDS patients, it is difficult to find common targets in studies with limited sample sizes. This study aimed to describe sequential molecular changes and identify biomarkers in MSC of MDS transformation.

METHODS

Multidimensional data from three publicly available microarray and TCGA datasets were analyzed. MDS-MSC was further isolated and cultured in vitro to determine the potential diagnostic and prognostic value of the identified biomarkers.

RESULTS

We demonstrated that normal MSCs presented greater molecular homogeneity than MDS-MSC. Biological process (embryonic skeletal system morphogenesis and angiogenesis) and pathways (p53 and MAPK) were enriched according to the differential gene expression. Furthermore, we identified HOXB3 and HOXB7 as potential causative genes gradually upregulated during the normal-MDS-AML transition. Blocking the HOXB3 and HOXB7 in MSCs could enhance the cell proliferation and differentiation, inhibit cell apoptosis and restore the function that supports hematopoietic differentiation in HSCs.

CONCLUSION

Our comprehensive study of gene expression profiling has identified dysregulated genes and biological processes in MSCs during MDS. HOXB3 and HOXB7 are proposed as novel surrogate targets for therapeutic and diagnostic applications in MDS.

Integrated Bioinformatics Analysis Reveals Diagnostic Biomarkers and Immune Cell Infiltration Characteristics of Solar Lentigines

Background

Solar lentigines (SLs), serving as a prevalent characteristic of skin photoaging, present as cutaneous aberrant pigmentation. However, the underlying pathogenesis remains unclear and there is a dearth of reliable diagnostic biomarkers.

Objective

The aim of this study was to identify diagnostic biomarkers for SLs and reveal its immunological features.

Methods

In this study, gene expression profiling datasets (GSE192564 and GSE192565) of SLs were obtained from the GEO database. The GSE192564 was used as the training group for screening of differentially expressed genes (DEGs) and subsequent depth analysis. Gene set enrichment analysis (GSEA) was employed to explore the biological states associated with SLs. The weighted gene co-expression network analysis (WGCNA) was employed to identify the significant modules and hub genes. Then, the feature genes were further screened by the overlapping of hub genes and up-regulated differential genes. Subsequently, an artificial neural network was constructed for identifying SLs samples. The GSE192565 was used as the test group for validation of feature genes expression level and the model's classification performance. Furthermore, we conducted immune cell infiltration analysis to reveal the immune infiltration landscape of SLs.

Results

The 9 feature genes were identified as diagnostic biomarkers for SLs in this study. And an artificial neural network based on diagnostic biomarkers was successfully constructed for identification of SLs. GSEA highlighted potential role of immune system in pathogenesis of SLs. SLs samples had a higher proportion of several immune cells, including activated CD8 T cell, dendritic cell, myeloid-derived suppressor cell and so on. And diagnostic biomarkers exhibited a strong relationship with the infiltration of most immune cells.

Conclusion

Our study identified diagnostic biomarkers for SLs and explored its immunological features, enhancing the comprehension of its pathogenesis.

Developmental and functional roles of androgen and interactive signals for external genitalia and erectile tissues

Background

Recent progress in molecular and signal analyses revealed essential functions of cellular signals including androgen and related growth factors such as Wnt regulators for external genitalia (ExG) development and its pathogenesis. Accumulated data showed their fundamental functions also for erectile tissue (corporal body) development and its abnormalities. The current review focuses on such signals from developmental and functional viewpoints.

Methods

Experimental strategies including histological and molecular signal analyses with conditional mutant mice for androgen and Wnt signals have been extensively utilized.

Main findings

Essential roles of androgen for the development of male-type ExG and urethral formation are shown. Wnt signals are associated with androgen for male-type ExG organogenesis. Androgen plays essential roles in the development of erectile tissue, the corporal body and it also regulates the duration time of erection. Wnt and other signals are essential for the regulation of mesenchymal cells of erectile tissue as shown by its conditional mutant mouse analyses. Stress signals, continuous erection, and the potential of lymphatic characteristics of the erectile vessels with sinusoids are also shown.

Conclusion

Reiterated involvement of androgen, Wnt, and other regulatory factors is stated for the development and pathogenesis of ExG and erectile tissues.

Pan-cancer analysis of homeodomain-containing gene C10 and its carcinogenesis in lung adenocarcinoma

We found elevated homeodomain-containing gene C10 (HOXC10) showed dual roles in cancers' prognosis. Some signal pathways associated with tumor were totally positively enriched in HOXC10 for whole cancers. On the contrary, Notch signaling, Wnt-beta catenin signaling, myogenesis, and Hedgehog signaling were almost negatively enriched in HOXC10. Some pathways showed dual roles such as Kras signaling, interferon gram and alpha response, IL6/JAK/STAT3, IL2/STAT5 signaling. HOXC10 was associated with tumor mutation burden and microsatellite instability. HOXC10 also was associated with tumor microenvironment and immune status. HOXC10 was negatively associated with immune score in most cancers except colon adenocarcinoma. The correlations of HOXC10 with immune-related genes presented dual roles in different cancers. Results from our clinical samples indicated that HOXC10 was an independent predictor for distant metastasis-free survival in lung adenocarcinoma (LUAD). Notably, the high levels of HOXC10 were positively correlated with the expression of angiogenic markers, vascular endothelial growth factor and microvessel density, and the number of CTC clusters. Our results demonstrated that aberrant expression happened in most cancers, which also affected the clinical prognosis and involved in progression via multiple signal pathways cancers. HOXC10 overexpression plays an important role in the aggression and metastasis in LUAD, which indicated a potential therapeutic target and an independent factor for the prognosis for LUAD patients.

The control of transitions along the main body axis

Although vertebrates display a large variety of forms and sizes, the mechanisms controlling the layout of the basic body plan are substantially conserved throughout the clade. Following gastrulation, head, trunk, and tail are sequentially generated through the continuous addition of tissue at the caudal embryonic end. Development of each of these major embryonic regions is regulated by a distinct genetic network. The transitions from head-to-trunk and from trunk-to-tail development thus involve major changes in regulatory mechanisms, requiring proper coordination to guarantee smooth progression of embryonic development. In this review, we will discuss the key cellular and embryological events associated with those transitions giving particular attention to their regulation, aiming to provide a cohesive outlook of this important component of vertebrate development.

HOXB3 promotes trophoblast cell proliferation, invasion, and migration to alleviate preeclampsia via mediating the Notch/Wnt/β-catenin pathway

Preeclampsia (PE) harms a significant number of pregnant women and fetuses. However, because of its complex pathological mechanisms, there is no cure except for delivery. This study identified the impact and mechanisms of action of HOXB3 in PE. The behaviors of HTR-8/SVneo cells were analyzed using a cell counting kit-8, EdU, and transwell assays. The interaction between HOXB3 and Notch1 was assessed using a luciferase reporter and chromatin immunoprecipitation assays. Expression was measured by quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence assays. Additionally, the function of HOXB3 was evaluated in an established rat model of PE. We found that HOXB3 was upregulated in PE. HOXB3 overexpression facilitated trophoblast cell proliferation, migration, and invasion. HOXB3 transcriptionally regulated Notch1 by binding to its promoter. Notch1 knockdown abrogated the functions of HOXB3 and the-catenin pathway in trophoblasts. Suppression of the Wnt/β-catenin pathway abrogated the effects of HOXB3. Additionally, HOXB3 alleviated the symptoms in PE rats. In conclusion, HOXB3 transcriptionally activated Notch1 expression and the-catenin pathway, promoting trophoblast cell proliferation, invasion, and migration, thereby alleviating PE progression. This study provides a novel approach for PE therapy.

Emerging questions on the mechanisms and dynamics of 3D genome evolution in spiralians

Information on how 3D genome topology emerged in animal evolution, how stable it is during development, its role in the evolution of phenotypic novelties and how exactly it affects gene expression is highly debated. So far, data to address these questions are lacking with the exception of a few key model species. Several gene regulatory mechanisms have been proposed, including scenarios where genome topology has little to no impact on gene expression, and vice versa. The ancient and diverse clade of spiralians may provide a crucial testing ground for such mechanisms. Sprialians have followed distinct evolutionary trajectories, with some clades experiencing genome expansions and/or large-scale genome rearrangements, and others undergoing genome contraction, substantially impacting their size and organisation. These changes have been associated with many phenotypic innovations in this clade. In this review, we describe how emerging genome topology data, along with functional tools, allow for testing these scenarios and discuss their predicted outcomes.

Comprehensive analysis of HOXC8 associated with tumor microenvironment characteristics in colorectal cancer

Background

Accumulating evidence have highlighted the essential roles of HOX genes in embryonic development and carcinogenesis. As a member of the HOX gene family, the abnormal expression of HOXC8 gene is associated with the progression and metastasis of various tumors. However, potential roles of HOXC8 in colorectal cancer (CRC) prognosis and tumor microenvironment (TME) remodeling remain unclear.

Methods

We conducted an integrated analysis of clinical and molecular characteristics, relevant oncogenic and immune regulation roles and drug sensitivity features of HOXC8 in CRC.

Results

HOXC8 expression was markedly high expressed in CRC samples compared to normal samples, and the upregulated expression of HOXC8 was associated with poor prognosis. High HOXC8 expression was significantly associated with invasion-related pathways especially epithelial-mesenchymal transition (EMT). In vitro experiments showed significantly up-regulated HOXC8 expression in some CRC cell lines and its promoting effect on EMT and cell proliferation. TME categorization through transcriptomic analysis of CRC patients with high HOXC8 expression identified two different TME subtypes known as immune-enriched with fibrotic subtype and immune-depleted subtype. Patients with immune-enriched, fibrotic subtype exhibited significantly longer progression-free survival (PFS), upregulated PD-L1 and CTLA4 expression and higher TMB than those with the immune-depleted subtype.

Conclusions

HOXC8 overexpression was associated with poor prognosis and specific TME subtypes in CRC. This study provided valuable resource for further exploring the potential mechanisms and therapeutic targets of HOX genes in CRC.

Associations between epigenome-wide DNA methylation and height-related traits among Sub-Saharan Africans: the RODAM study

Human height and related traits are highly complex, and extensively research has shown that these traits are determined by both genetic and environmental factors. Such factors may partially affect these traits through epigenetic programing. Epigenetic programing is dynamic and plays an important role in controlling gene expression and cell differentiation during (early) development. DNA methylation (DNAm) is the most commonly studied epigenetic feature. In this study we conducted an epigenome-wide DNAm association analysis on height-related traits in a Sub-Saharan African population, in order to detect DNAm biomarkers across four height-related traits. DNAm profiles were acquired in whole blood samples of 704 Ghanaians, sourced from the Research on Obesity and Diabetes among African Migrants study, using the Illumina Infinium HumanMethylation450 BeadChip. Linear models were fitted to detect differentially methylated positions (DMPs) and regions (DMRs) associated with height, leg-to-height ratio (LHR), leg length, and sitting height. No epigenome-wide significant DMPs were recorded. However we did observe among our top DMPs five informative probes associated with the height-related traits: cg26905768 (leg length), cg13268132 (leg length), cg19776793 (height), cg23072383 (LHR), and cg24625894 (sitting height). All five DMPs are annotated to genes whose functions were linked to bone cell regulation and development. DMR analysis identified overlapping DMRs within the gene body of HLA-DPB1 gene, and the HOXA gene cluster. In this first epigenome-wide association studies of these traits, our findings suggest DNAm associations with height-related heights, and might influence development and maintenance of these traits. Further studies are needed to replicate our findings, and to elucidate the molecular mechanism underlying human height-related traits.

Fgf signalling triggers an intrinsic mesodermal timer that determines the duration of limb patterning

Complex signalling between the apical ectodermal ridge (AER - a thickening of the distal epithelium) and the mesoderm controls limb patterning along the proximo-distal axis (humerus to digits). However, the essential in vivo requirement for AER-Fgf signalling makes it difficult to understand the exact roles that it fulfils. To overcome this barrier, we developed an amenable ex vivo chick wing tissue explant system that faithfully replicates in vivo parameters. Using inhibition experiments and RNA-sequencing, we identify a transient role for Fgfs in triggering the distal patterning phase. Fgfs are then dispensable for the maintenance of an intrinsic mesodermal transcriptome, which controls proliferation/differentiation timing and the duration of patterning. We also uncover additional roles for Fgf signalling in maintaining AER-related gene expression and in suppressing myogenesis. We describe a simple logic for limb patterning duration, which is potentially applicable to other systems, including the main body axis.

The identification, adaptive evolutionary analyses and mRNA expression levels of homeobox (hox) genes in the Chinese mitten crab Eriocheir sinensis

BACKGROUND

Arthropods are the largest group in the animal kingdom and are morphologically characterized by heterorhythmic segments. Brachyuran decapod crustaceans undergo brachyurization metamorphosis in the early developmental process, characterized by a reduced abdomen that is folded beneath the cephalothorax and inserted between the pereiopods or in a special cavity. As the main cause of major alterations in the evolution of animal body plans, Hox genes encode transcription factors and are involved in bilaterian anterior-posterior axis patterning.

RESULTS

We found eight Hox genes (labial, proboscipedia, Deformed, zerknüllt, Sex combs reduced, Antennapedia, Ultrabithorax, fushi tarazu, abdominal-A and Abdominal-B) in Eriocheir sinensis. The phylogenetic topology of 13 arthropod Hox genes was closely related to traditional taxonomic groupings. Genome collinearity analysis was performed using genomic data and chromosomal location data of E. sinensis and Portunus trituratus. We found that their chromosomes were highly collinear, and there was a corresponding collinear relationship between the three Hox genes (lab, ftz and Abd-B). The mRNA expression levels of Scr and Antp fluctuated significantly in different developmental stages of E. sinensis, especially in the brachyurization stages. Evolutionary analysis indicated the presence of positively selected sites in Ubx.

CONCLUSIONS

In this study, we used genome-wide analysis to identify and analyze all members of the Hox genes in E. sinensis. Our data will contribute to a better understanding of Hox genes in E. sinensis and provide useful molecular evolutionary information for further investigation on their roles in the brachyurization of crabs.

Culture conditions of mouse ESCs impact the tumor appearance in vivo

Various culture conditions by small molecules have been explored to extend pluripotency of stem cells, but their impacts on cell fate in vivo remain elusive. We systematically compared the effects of various culture conditions on the pluripotency and cell fate in vivo of mouse embryonic stem cells (ESCs) by tetraploid embryo complementation assay. Conventional ESC cultures in serum/LIF-based condition produced complete ESC mice and also the survival to adulthood at the highest rates of all other chemical-based cultures. Moreover, long-term examination of the survived ESC mice demonstrated that conventional ESC cultures did not lead to visible abnormality for up to 1.5-2 years, whereas the prolonged chemical-based cultures developed retroperitoneal atypical teratomas or leiomyomas. The chemical-based cultures exhibited transcriptomes and epigenomes that typically differed from those of conventional ESC cultures. Our results warrant further refinement of culture conditions in promoting the pluripotency and safety of ESCs in future applications.

Spinal Cord Organoids to Study Motor Neuron Development and Disease

Motor neuron diseases (MNDs) are a heterogeneous group of disorders that affect the cranial and/or spinal motor neurons (spMNs), spinal sensory neurons and the muscular system. Although they have been investigated for decades, we still lack a comprehensive understanding of the underlying molecular mechanisms; and therefore, efficacious therapies are scarce. Model organisms and relatively simple two-dimensional cell culture systems have been instrumental in our current knowledge of neuromuscular disease pathology; however, in the recent years, human 3D in vitro models have transformed the disease-modeling landscape. While cerebral organoids have been pursued the most, interest in spinal cord organoids (SCOs) is now also increasing. Pluripotent stem cell (PSC)-based protocols to generate SpC-like structures, sometimes including the adjacent mesoderm and derived skeletal muscle, are constantly being refined and applied to study early human neuromuscular development and disease. In this review, we outline the evolution of human PSC-derived models for generating spMN and recapitulating SpC development. We also discuss how these models have been applied to exploring the basis of human neurodevelopmental and neurodegenerative diseases. Finally, we provide an overview of the main challenges to overcome in order to generate more physiologically relevant human SpC models and propose some exciting new perspectives.

3D genomics and its applications in precision medicine

Three-dimensional (3D) genomics is an emerging discipline that studies the three-dimensional structure of chromatin and the three-dimensional and functions of genomes. It mainly studies the three-dimensional conformation and functional regulation of intranuclear genomes, such as DNA replication, DNA recombination, genome folding, gene expression regulation, transcription factor regulation mechanism, and the maintenance of three-dimensional conformation of genomes. Self-chromosomal conformation capture (3C) technology has been developed, and 3D genomics and related fields have developed rapidly. In addition, chromatin interaction analysis techniques developed by 3C technologies, such as paired-end tag sequencing (ChIA-PET) and whole-genome chromosome conformation capture (Hi-C), enable scientists to further study the relationship between chromatin conformation and gene regulation in different species. Thus, the spatial conformation of plant, animal, and microbial genomes, transcriptional regulation mechanisms, interaction patterns of chromosomes, and the formation mechanism of spatiotemporal specificity of genomes are revealed. With the help of new experimental technologies, the identification of key genes and signal pathways related to life activities and diseases is sustaining the rapid development of life science, agriculture, and medicine. In this paper, the concept and development of 3D genomics and its application in agricultural science, life science, and medicine are introduced, which provides a theoretical basis for the study of biological life processes.

Homeobox Genes in Odontogenic Lesions: A Scoping Review

BACKGROUND

Homeobox genes play crucial roles in tooth morphogenesis and development and thus mutations in homeobox genes cause developmental disorders such as odontogenic lesions. The aim of this scoping review is to identify and compile available data from the literatures on the topic of homeobox gene expression in odontogenic lesions.

METHOD

An electronic search to collate all the information on studies on homeobox gene expression in odontogenic lesions was carried out in four databases (PubMed, EBSCO host, Web of Science and Cochrane Library) with selected keywords. All papers which reported expression of homeobox genes in odontogenic lesions were considered.

RESULTS

A total of eleven (11) papers describing expression of homeobox genes in odontogenic lesions were identified. Methods of studies included next generation sequencing, microarray analysis, RT-PCR, Western blotting, in situ hybridization, and immunohistochemistry. The homeobox reported in odontogenic lesions includes LHX8 and DLX3 in odontoma; PITX2, MSX1, MSX2, DLX, DLX2, DLX3, DLX4, DLX5, DLX6, ISL1, OCT4 and HOX C in ameloblastoma; OCT4 in adenomatoid odontogenic tumour; PITX2 and MSX2 in primordial odontogenic tumour; PAX9 and BARX1 in odontogenic keratocyst; PITX2, ZEB1 and MEIS2 in ameloblastic carcinoma while there is absence of DLX2, DLX3 and MSX2 in clear cell odontogenic carcinoma.

CONCLUSIONS

This paper summarized and reviews the possible link between homeobox gene expression in odontogenic lesions. Based on the current available data, there are insufficient evidence to support any definite role of homeobox gene in odontogenic lesions.

BdNub Is Essential for Maintaining gut Immunity and Microbiome Homeostasis in Bactrocera dorsalis

Insects face immune challenges posed by invading and indigenous bacteria. They rely on the immune system to clear these microorganisms. However, the immune response can be harmful to the host. Therefore, fine-tuning the immune response to maintain tissue homeostasis is of great importance to the survival of insects. The Nub gene of the OCT/POU family regulates the intestinal IMD pathway. However, the role of the Nub gene in regulating host microbiota remains unstudied. Here, a combination of bioinformatic tools, RNA interference, and qPCR methods were adopted to study BdNub gene function in Bactrocera dorsalis gut immune system. It's found that BdNubX1, BdNubX2, and antimicrobial peptides (AMPs), including Diptcin (Dpt), Cecropin (Cec), AttcinA (Att A), AttcinB (Att B) and AttcinC (Att C) are significantly up-regulated in Tephritidae fruit fly Bactrocera dorsalis after gut infection. Silencing BdNubX1 leads to down-regulated AMPs expression, while BdNubX2 RNAi leads to increased expression of AMPs. These results indicate that BdNubX1 is a positive regulatory gene of the IMD pathway, while BdNubX2 negatively regulates IMD pathway activity. Further studies also revealed that BdNubX1 and BdNubX2 are associated with gut microbiota composition, possibly through regulation of IMD pathway activity. Our results prove that the Nub gene is evolutionarily conserved and participates in maintaining gut microbiota homeostasis.

A Live Cell Protein Complementation Assay for ORFeome-Wide Probing of Human HOX Interactomes

Biological pathways rely on the formation of intricate protein interaction networks called interactomes. Getting a comprehensive map of interactomes implies the development of tools that allow one to capture transient and low-affinity protein-protein interactions (PPIs) in live conditions. Here we presented an experimental strategy: the Cell-PCA (cell-based protein complementation assay), which was based on bimolecular fluorescence complementation (BiFC) for ORFeome-wide screening of proteins that interact with different bait proteins in the same live cell context, by combining high-throughput sequencing method. The specificity and sensitivity of the Cell-PCA was established by using a wild-type and a single-amino-acid-mutated HOXA9 protein, and the approach was subsequently applied to seven additional human HOX proteins. These proof-of-concept experiments revealed novel molecular properties of HOX interactomes and led to the identification of a novel cofactor of HOXB13 that promoted its proliferative activity in a cancer cell context. Taken together, our work demonstrated that the Cell-PCA was pertinent for revealing and, importantly, comparing the interactomes of different or highly related bait proteins in the same cell context.

Hox genes in development and beyond

Hox genes encode evolutionarily conserved transcription factors that are essential for the proper development of bilaterian organisms. Hox genes are unique because they are spatially and temporally regulated during development in a manner that is dictated by their tightly linked genomic organization. Although their genetic function during embryonic development has been interrogated, less is known about how these transcription factors regulate downstream genes to direct morphogenetic events. Moreover, the continued expression and function of Hox genes at postnatal and adult stages highlights crucial roles for these genes throughout the life of an organism. Here, we provide an overview of Hox genes, highlighting their evolutionary history, their unique genomic organization and how this impacts the regulation of their expression, what is known about their protein structure, and their deployment in development and beyond.

LncRNA HOTAIR impairs the prognosis of papillary thyroid cancer via regulating cellular malignancy and epigenetically suppressing DLX1

PURPOSE

Papillary thyroid cancer (PTC) is the most common endocrine malignancy with a fast-growing incidence in recent decades. HOTAIR as a long non-coding RNA has been shown to be highly expressed in papillary thyroid cancer tissues with only a limited understanding of its functional roles and downstream regulatory mechanisms in papillary thyroid cancer cells.

METHODS

We applied three thyroid cancer cell lines (MDA-T32, MDA-T41 and K1) to investigate the phenotypic influence after gain or loss of HOTAIR. The Cancer Genome Atlas (TCGA) database were utilised to select candidate genes possibly regulated by HOTAIR with validation in the cellular system and immunohistochemical (IHC) staining of PTC tissues.

RESULTS

We observed HOTAIR was highly expressed in MDA-T32 cells but presents significantly decreased levels in MDA-T41 and K1 cells. HOTAIR knockdown in MDA-T32 cells significantly suppressed proliferation, colony formation, migration with cell cycle retardation at G1 phase. On the contrary, HOTAIR overexpression in MDA-T41 cells dramatically enhanced proliferation, colony formation, migration with cell cycle driven toward S and G2/M phases. Similar phenotypic effects were also observed as overexpressing HOTAIR in K1 cells. To explore novel HOTAIR downstream mechanisms, we analyzed TCGA transcriptome in PTC tissues and found DLX1 negatively correlated to HOTAIR, and its lower expression associated with reduced progression free survival. We further validated DLX1 gene was epigenetically suppressed by HOTAIR via performing chromatin immunoprecipitation. Moreover, IHC staining shows a significantly stepwise decrease of DLX1 protein from normal thyroid tissues to stage III PTC tissues.

CONCLUSIONS

Our study pointed out that HOTAIR is a key regulator of cellular malignancy and its epigenetic suppression on DLX1 serves as a novel biomarker to evaluate the PTC disease progression.

Shaping Hox gene activity to generate morphological diversity across vertebrate phylogeny

The importance of Hox genes for the development and evolution of the vertebrate axial skeleton and paired appendages has been recognized for already several decades. The steady growth of genomic sequence data from an increasing number of vertebrate species, together with the improvement of methods to analyze genomic structure and interactions, as well as to control gene activity in various species has refined our understanding of Hox gene activity in development and evolution. Here, I will review recent data addressing the influence of Hox regulatory processes in the evolution of the fins and the emergence of the tetrapod limb. In addition, I will discuss the involvement of posterior Hox genes in the control of vertebrate axial extension, focusing on an apparently divergent activity that Hox13 paralog group genes have on the regulation of tail bud development in mouse and zebrafish embryos.

Regeneration of the human segmentation clock in somitoids in vitro

Each vertebrate species appears to have a unique timing mechanism for forming somites along the vertebral column, and the process in human remains poorly understood at the molecular level due to technical and ethical limitations. Here, we report the reconstitution of human segmentation clock by direct reprogramming. We first reprogrammed human urine epithelial cells to a presomitic mesoderm (PSM) state capable of long-term self-renewal and formation of somitoids with an anterior-to-posterior axis. By inserting the RNA reporter Pepper into HES7 and MESP2 loci of these iPSM cells, we show that both transcripts oscillate in the resulting somitoids at ~5 h/cycle. GFP-tagged endogenous HES7 protein moves along the anterior-to-posterior axis during somitoid formation. The geo-sequencing analysis further confirmed anterior-to-posterior polarity and revealed the localized expression of WNT, BMP, FGF, and RA signaling molecules and HOXA-D family members. Our study demonstrates the direct reconstitution of human segmentation clock from somatic cells, which may allow future dissection of the mechanism and components of such a clock and aid regenerative medicine.

Developmental disruption and restoration of brain synaptome architecture in the murine Pax6 neurodevelopmental disease model

Neurodevelopmental disorders of genetic origin delay the acquisition of normal abilities and cause disabling phenotypes. Nevertheless, spontaneous attenuation and even complete amelioration of symptoms in early childhood and adolescence can occur in many disorders, suggesting that brain circuits possess an intrinsic capacity to overcome the deficits arising from some germline mutations. We examined the molecular composition of almost a trillion excitatory synapses on a brain-wide scale between birth and adulthood in mice carrying a mutation in the homeobox transcription factor Pax6, a neurodevelopmental disorder model. Pax6 haploinsufficiency had no impact on total synapse number at any age. By contrast, the molecular composition of excitatory synapses, the postnatal expansion of synapse diversity and the acquisition of normal synaptome architecture were delayed in all brain regions, interfering with networks and electrophysiological simulations of cognitive functions. Specific excitatory synapse types and subtypes were affected in two key developmental age-windows. These phenotypes were reversed within 2-3 weeks of onset, restoring synapse diversity and synaptome architecture to the normal developmental trajectory. Synapse subtypes with rapid protein turnover mediated the synaptome remodeling. This brain-wide capacity for remodeling of synapse molecular composition to recover and maintain the developmental trajectory of synaptome architecture may help confer resilience to neurodevelopmental genetic disorders.

BAP1 in cancer: epigenetic stability and genome integrity

Mutations in BAP1 have been identified in a hereditary cancer predisposition syndrome and in sporadic tumours. Individuals carrying familiar BAP1 monoallelic mutations display hypersusceptibility to exposure-associated cancers, such as asbestos-driven mesothelioma, thus BAP1 status has been postulated to participate in gene-environment interaction. Intriguingly, BAP1 functions display also a high degree of tissue dependency, associated to a peculiar cancer spectrum and cell types of specific functions. Mechanistically, BAP1 functions as an ubiquitin carboxy-terminal hydrolase (UCH) and controls regulatory ubiquitination of histones as well as degradative ubiquitination of a range of protein substrates. In this article we provide an overview of the most relevant findings on BAP1, underpinning its tissue specific tumour suppressor function. We also discuss the importance of its epigenetic role versus the control of protein stability in the regulation of genomic integrity.

Comprehensive analysis of a homeobox family gene signature in clear cell renal cell carcinoma with regard to prognosis and immune significance

The homeobox (HOX) family genes have been linked to multiple types of tumors, while their effect on malignant behaviors of clear cell renal cell carcinoma (ccRCC) and clinical significance remains largely unknown. Here, we comprehensively analyzed the expression profiles and prognostic value of HOX genes in ccRCC using datasets from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. We developed a prognostic signature comprising eight HOX genes (HOXB1, HOXA7, HOXB5, HOXD8, HOXD9, HOXB9, HOXA9, and HOXA11) for overall survival prediction in ccRCC and it allowed patients to be subdivided into high- and low-risk groups. Kaplan-Meier survival analysis in all the internal and external cohorts revealed significant difference in clinical outcome of patients in different risk groups, indicating the satisfactory predictive power of the signature. Additionally, we constructed a prognostic nomogram by integrating signature-derived risk score and clinical factors such as gender, age, T and M status, which might be helpful for clinical decision-making and designing tailored management schedules. Immunological analysis revealed that the regulatory T cells (Tregs) infiltrated differently between the two subgroups in both TCGA and ICGC cohorts. ssGSEA method showed that the enrichment scores for mast cells were significantly lower in high-risk group compared with the low-risk group, which was consistent in both TCGA and ICGC cohorts. As for the related immune function, the enrichment scores of APC co-inhibition, para-inflammation, and type II IFN response were consistently lower in high-risk group in both cohorts. Of the eight HOX genes, the mRNA and protein levels of HOXD8 were downregulated in ccRCC than that in normal tissues, and decreased expression of HOXD8 was associated with increased tumor grade and stage, and lymph node metastasis. Survival analysis revealed that lower expression of HOXD8 predicted worse overall survival in ccRCC. In conclusion, our HOX gene-based signature was a favorable indicator to predict the prognosis of ccRCC cases and associated with immune cell infiltration. HOXD8 might be a tumor suppressor gene in ccRCC and a potential predictor of tumor progression.

Pluripotency factors regulate the onset of Hox cluster activation in the early embryo

Pluripotent cells are a transient population of the mammalian embryo dependent on transcription factors, such as OCT4 and NANOG, which maintain pluripotency while suppressing lineage specification. However, these factors are also expressed during early phases of differentiation, and their role in the transition from pluripotency to lineage specification is largely unknown. We found that pluripotency factors play a dual role in regulating key lineage specifiers, initially repressing their expression and later being required for their proper activation. We show that Oct4 is necessary for activation of HoxB genes during differentiation of embryonic stem cells and in the embryo. In addition, we show that the HoxB cluster is coordinately regulated by OCT4 binding sites located at the 3' end of the cluster. Our results show that core pluripotency factors are not limited to maintaining the precommitted epiblast but are also necessary for the proper deployment of subsequent developmental programs.

DNA Methylation of HOXA11 Gene as Prognostic Molecular Marker in Human Gastric Adenocarcinoma

Hypermethylation of tumor suppressor genes and hypomethylation of oncogenes might be identified as possible biomarkers in gastric cancer (GC). We aimed to assess the DNA methylation status of selected genes in GC tissue samples and evaluate these genes’ prognostic importance on patient survival. Patients (99) diagnosed with GC and who underwent gastrectomy were included. We selected a group of genes (RAD51B, GFRA3, AKR7A3, HOXA11, TUSC3, FLI1, SEZ6L, GLDC, NDRG) which may be considered as potential tumor suppressor genes and oncogenes. Methylation of the HOXA11 gene promoter was significantly more frequent in GC tumor tissue (p = 0.006) than in healthy gastric mucosa. The probability of surviving longer (71.2 months (95% CI 57–85.3) vs. 44.3 months (95% CI 34.8–53.9)) was observed with unmethylated HOXA11 promoter in cancer tissues. Survival in patients with a methylation of HOXA11 promoter either in healthy gastric mucosa or gastric cancer tissue was twice as high as in patients with a methylation of HOXA11 promoter in both healthy gastric mucosa and cancer tissue (61.2 months (95% CI 50.9–71.4) vs. 28.5 months (95% CI 20.8–36.2)). Multivariate Cox analysis revealed the HOXA11 methylation as significantly associated with patients’ survival (HR = 2.4, 95% CI 1.19–4.86). Our results suggest that the HOXA11 gene might be a potential prognostic molecular marker in patients with gastric adenocarcinoma.

Embryology of the Abdominal Wall and Associated Malformations—A Review

In humans, the incidence of congenital defects of the intraembryonic celom and its associated structures has increased over recent decades. Surgical treatment of abdominal and diaphragmatic malformations resulting in congenital hernia requires deep knowledge of ventral body closure and the separation of the primary body cavities during embryogenesis. The correct development of both structures requires the coordinated and fine-tuned synergy of different anlagen, including a set of molecules governing those processes. They have mainly been investigated in a range of vertebrate species (e.g., mouse, birds, and fish), but studies of embryogenesis in humans are rather rare because samples are seldom available. Therefore, we have to deal with a large body of conflicting data concerning the formation of the abdominal wall and the etiology of diaphragmatic defects. This review summarizes the current state of knowledge and focuses on the histological and molecular events leading to the establishment of the abdominal and thoracic cavities in several vertebrate species. In chronological order, we start with the onset of gastrulation, continue with the establishment of the three-dimensional body shape, and end with the partition of body cavities. We also discuss well-known human etiologies.

A fishy tail: Insights into the cell and molecular biology of neuromesodermal cells from zebrafish embryos

Vertebrate embryos establish their primary body axis in a conserved progressive fashion from the anterior to the posterior. During this process, a posteriorly localized neuromesodermal cell population called neuromesodermal progenitors (NMps) plays a critical role in contributing new cells to the spinal cord and mesoderm as the embryo elongates. Defects in neuromesodermal population development can cause severe disruptions to the formation of the body posterior to the head. Given their importance during development and their potential, some of which has already been realized, for revealing new methods of in vitro tissue generation, there is great interest in better understanding NMp biology. The zebrafish model system has been instrumental in advancing our understanding of the molecular and cellular attributes of the NM cell population and its derivatives. In this review, we focus on our current understanding of the zebrafish NM population and its contribution to body axis formation, with particular emphasis on the lineage potency, morphogenesis, and niche factors that promote or inhibit differentiation.

Mesoderm induction and patterning: Insights from neuromesodermal progenitors

The discovery of mesoderm inducing signals helped usher in the era of molecular developmental biology, and today the mechanisms of mesoderm induction and patterning are still intensely studied. Mesoderm induction begins during gastrulation, but recent evidence in vertebrates shows that this process continues after gastrulation in a group of posteriorly localized cells called neuromesodermal progenitors (NMPs). NMPs reside within the post-gastrulation embryonic structure called the tailbud, where they make a lineage decision between ectoderm (spinal cord) and mesoderm. The majority of NMP-derived mesoderm generates somites, but also contributes to lateral mesoderm fates such as endothelium. The discovery of NMPs provides a new paradigm in which to study vertebrate mesoderm induction. This review will discuss mechanisms of mesoderm induction within NMPs, and how they have informed our understanding of mesoderm induction more broadly within vertebrates as well as animal species outside of the vertebrate lineage. Special focus will be given to the signaling networks underlying NMP-derived mesoderm induction and patterning, as well as emerging work on the significance of partial epithelial-mesenchymal states in coordinating cell fate and morphogenesis.

Whole genome sequencing of Luxi Black Head sheep for screening selection signatures associated with important traits

Objective

Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH.

Methods

We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genome-wide selection signatures have been scanned with four methods: heterozygosity (H_P), fixation index (F_ST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (θ_π) ratio.

Results

The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected.

Conclusion

The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

Regulation of posterior Hox genes by sex steroids explains vertebral variation in inbred mouse strains

A series of elegant embryo transfer experiments in the 1950s demonstrated that the uterine environment could alter vertebral patterning in inbred mouse strains. In the intervening decades, attention has tended to focus on the technical achievements involved and neglected the underlying biological question: how can genetically homogenous individuals have a heterogenous number of vertebrae? Here I revisit these experiments and, with the benefit of knowledge of the molecular-level processes of vertebral patterning gained over the intervening decades, suggest a novel hypothesis for homeotic transformation of the last lumbar vertebra to the adjacent sacral type through regulation of Hox genes by sex steroids. Hox genes are involved in both axial patterning and development of male and female reproductive systems and have been shown to be sensitive to sex steroids in vitro and in vivo. Regulation of these genes by sex steroids and resulting alterations to vertebral patterning may hint at a deep evolutionary link between the ribless lumbar region of mammals and the switch from egg-laying to embryo implantation. An appreciation of the impact of sex steroids on Hox genes may explain some puzzling aspects of human disease, and highlights the spine as a neglected target for in utero exposure to endocrine disruptors.

Molecular implications of HOX genes targeting multiple signaling pathways in cancer

Homeobox (HOX) genes encode highly conserved homeotic transcription factors that play a crucial role in organogenesis and tissue homeostasis. Their deregulation impacts the function of several regulatory molecules contributing to tumor initiation and progression. A functional bridge exists between altered gene expression of individual HOX genes and tumorigenesis. This review focuses on how deregulation in the HOX-associated signaling pathways contributes to the metastatic progression in cancer. We discuss their functional significance, clinical implications and ascertain their role as a diagnostic and prognostic biomarker in the various cancer types. Besides, the mechanism of understanding the theoretical underpinning that affects HOX-mediated therapy resistance in cancers has been outlined. The knowledge gained shall pave the way for newer insights into the treatment of cancer.

Epigenetic regulation by long noncoding RNAs in osteo-/adipogenic differentiation of mesenchymal stromal cells and degenerative bone diseases

Bone is a complex tissue that undergoes constant remodeling to maintain homeostasis, which requires coordinated multilineage differentiation and proper proliferation of mesenchymal stromal cells (MSCs). Mounting evidence indicates that a disturbance of bone homeostasis can trigger degenerative bone diseases, including osteoporosis and osteoarthritis. In addition to conventional genetic modifications, epigenetic modifications (i.e., DNA methylation, histone modifications, and the expression of noncoding RNAs) are considered to be contributing factors that affect bone homeostasis. Long noncoding RNAs (lncRNAs) were previously regarded as ‘transcriptional noise’ with no biological functions. However, substantial evidence suggests that lncRNAs have roles in the epigenetic regulation of biological processes in MSCs and related diseases. In this review, we summarized the interactions between lncRNAs and epigenetic modifiers associated with osteo-/adipogenic differentiation of MSCs and the pathogenesis of degenerative bone diseases and highlighted promising lncRNA-based diagnostic and therapeutic targets for bone diseases.

Screening and verification of potential gene targets in esophageal carcinoma by bioinformatics analysis and immunohistochemistry

Background

To evaluate the potential of candidate proteins as diagnostic markers or drug targets in esophageal carcinoma (ESCA).

Methods

GSE20347, GSE17351, and GSE45670 were downloaded from Gene Expression Omnibus (GEO). Differently expressed genes (DEGs) between ESCA and normal esophageal tissues from patients were obtained. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed. The genes commonly featured in ESCA were screened by least absolute shrinkage and selection operator (LASSO) logistic regression and Boruta feature selection algorithm. The transcriptome data and corresponding clinical data of ESCA were downloaded from The Cancer Genome Atlas (TCGA) public database. Kaplan-Meier survival analysis was used to explore the core genes related to the prognosis of patients. A protein-protein interaction (PPI) network was generated by GeneMANIA to visualize the functional network between genes. Expressions of CRIP2, FOS, and HOXA10 genes in ESCA cells were verified by immunohistochemistry (IHC).

Results

Out of 11,207 genes, 430 DEGs were identified, including 210 up-regulated genes and 220 down-regulated genes. After taking the intersection of LASSO regression and Boruta algorithm, 15 core genes were identified. Survival analyses demonstrated that low expression of CRIP2 (P=2.643e-02), as well as high expression of FOS (P=4.837e-02) and HOXA10 (P=4.97e-02), was significantly associated with the worse prognosis of ESCA patients. The 3 genes were strongly correlated with the content of immune cells and the stage of tumors. The expression of CRIP2 was correlated with the sensitivity of patients to dasatinib; FOS expression was correlated with the sensitivity of patients to erlotinib, and HOXA10 expression affected the sensitivity of patients to cisplatin, dasatinib, erlotinib, and gefitinib. The cBioportal database showed that 56 patients (31%) had the above core gene mutations: CRIP2 (8%), FOS (10%), and HOXA10 (17%). The IHC showed that there were differences in the expressions of these core genes between ESCA patients and the normal population (P<0.05), with ESCA patients showing higher expression.

Conclusions

The low CRIP2 expression and high expressions of FOS and HOXA10 are associated with more advanced tumor stage, which may have the potential to be novel biomarkers for treatment selection in ESCA.

Three topological features of regulatory networks control life-essential and specialized subsystems

Gene regulatory networks (GRNs) play key roles in development, phenotype plasticity, and evolution. Although graph theory has been used to explore GRNs, associations amongst topological features, transcription factors (TFs), and systems essentiality are poorly understood. Here we sought the relationship amongst the main GRN topological features that influence the control of essential and specific subsystems. We found that the K_nn, page rank, and degree are the most relevant GRN features: the ones are conserved along the evolution and are also relevant in pluripotent cells. Interestingly, life-essential subsystems are governed mainly by TFs with intermediary K_nn and high page rank or degree, whereas specialized subsystems are mainly regulated by TFs with low K_nn. Hence, we suggest that the high probability of TFs be toured by a random signal, and the high probability of the signal propagation to target genes ensures the life-essential subsystems' robustness. Gene/genome duplication is the main evolutionary process to rise K_nn as the most relevant feature. Herein, we shed light on unexplored topological GRN features to assess how they are related to subsystems and how the duplications shaped the regulatory systems along the evolution. The classification model generated can be found here: https://github.com/ivanrwolf/NoC/ .

Somite development and regionalisation of the vertebral axial skeleton

A critical stage in the development of all vertebrate embryos is the generation of the body plan and its subsequent patterning and regionalisation along the main anterior-posterior axis. This includes the formation of the vertebral axial skeleton. Its organisation begins during early embryonic development with the periodic formation of paired blocks of mesoderm tissue called somites. Here, we review axial patterning of somites, with a focus on studies using amniote model systems - avian and mouse. We summarise the molecular and cellular mechanisms that generate paraxial mesoderm and review how the different anatomical regions of the vertebral column acquire their specific identity and thus shape the body plan. We also discuss the generation of organoids and embryo-like structures from embryonic stem cells, which provide insights regarding axis formation and promise to be useful for disease modelling.