Developmental Progression Research Articles

Developing mathematical patterning in ECE classrooms: participatory research with teachers of 3–5-year-olds

ABSTRACT Research shows that attention to pattern and structure is fundamental to mathematical learning and attainment yet early mathematics curricula in England underplay the importance of patterning. In a critical realist notion of powerful knowledge, pattern teaching has the potential to empower children to notice patterns, mathematise their everyday experiences and engage in mathematical sense-making. This study investigated how to harness this potential. It reports on participatory research with ten teachers of three to five-year-old children in England as they developed pattern teaching in their classrooms. Findings indicate that teacher knowledge, pedagogic interactions and pattern-rich environments (all underpinned by an appropriate developmental progression and extended to form a setting-wide shared approach) support the development of patterning praxis in early childhood classrooms. These offer potential priorities for ECE teachers in developing their patterning praxis in order to support children’s mathematical learning.

Assessment of neurosurgical resident milestone evaluation reporting and feedback processes.

Structured performance evaluations are important for the professional development and personal growth of resident learners. This process is formalized by the Accreditation Council for Graduate Medical Education milestones assessment system. The primary aim of this study was to understand the current feedback delivery mechanism by exploring the culture of feedback, the mechanics of delivery, and the evaluation of the feedback itself. Face-to-face interviews were conducted with 10 neurosurgery residents exploring their perceptions of summative feedback. Coded data were analyzed qualitatively for overriding themes using the matrix framework method. A priori themes of definition of feedback, feedback delivery, and impact of feedback were combined with de novo themes discovered during analysis. Trainees prioritized formative over summative feedback. Summative and milestone feedback were criticized as being vague, misaligned with practice, and often perceived as erroneous. Barriers to implementation of summative feedback included perceived veracity of feedback, high interrater variability, and the inconstant adoption of a developmental progression model. Gender bias was noted in degree of feedback provided and language used. Trainee perception of feedback provided multiple areas of improvement. This paper can serve as a baseline to study improvements in the milestone feedback process and optimize learning.

Rap1 controls epiblast morphogenesis in sync with the pluripotency states transition

The complex architecture of the murine fetus originates from a simple ball of pluripotent epiblast cells, which initiate morphogenesis upon implantation. In turn, this establishes an intermediate state of tissue-scale organization of the embryonic lineage in the form of an epithelial monolayer, where patterning signals delineate the body plan. However, how this major morphogenetic process is orchestrated on a cellular level and synchronized with the developmental progression of the epiblast is still obscure. Here, we identified that the small GTPase Rap1 plays a critical role in reshaping the pluripotent lineage. We found that Rap1 activity is controlled via Oct4/Esrrb input and is required for the transmission of polarization cues, which enables the de novo epithelialization and formation of tricellular junctions in the epiblast. Thus, Rap1 acts as a molecular switch that coordinates the morphogenetic program in the embryonic lineage, in sync with the cellular states of pluripotency.

Assessing Well-Being in Milestones 2.0: A Case for Flourishing-Focused Advising.

Assessing Well-Being in Milestones 2.0: A Case for Flourishing-Focused Advising.

Single-cell transcriptomics reveals male germ cells and Sertoli cells developmental patterns in dairy goats.

Spermatogenesis holds considerable promise for human-assisted reproduction and livestock breeding based on stem cells. It occurs in seminiferous tubules within the testis, which mainly comprise male germ cells and Sertoli cells. While the developmental progression of male germ cells and Sertoli cells has been widely reported in mice, much less is known in other large animal species, including dairy goats. In this study, we present the data of single cell RNA sequencing (scRNA-seq) for 25,373 cells from 45 (pre-puberty), 90 (puberty), and 180-day-old (post-puberty) dairy goat testes. We aimed to identify genes that are associated with key developmental events in male germ cells and Sertoli cells. We examined the development of spermatogenic cells and seminiferous tubules from 15, 30, 45, 60, 75, 90, 180, and 240-day-old buck goat testes. scRNA-seq clustering analysis of testicular cells from pre-puberty, puberty, and post-puberty goat testes revealed several cell types, including cell populations with characteristics of spermatogonia, early spermatocytes, spermatocytes, spermatids, Sertoli cells, Leydig cells, macrophages, and endothelial cells. We mapped the timeline for male germ cells development from spermatogonia to spermatids and identified gene signatures that define spermatogenic cell populations, such as AMH, SOHLH1, INHA, and ACTA2. Importantly, using immunofluorescence staining for different marker proteins (UCHL1, C-KIT, VASA, SOX9, AMH, and PCNA), we explored the proliferative activity and development of male germ cells and Sertoli cells. Moreover, we identified the expression patterns of potential key genes associated with the niche-related key pathways in male germ cells of dairy goats, including testosterone, retinoic acid, PDGF, FGF, and WNT pathways. In summary, our study systematically investigated the elaborate male germ cells and Sertoli cells developmental patterns in dairy goats that have so far remained largely unknown. This information represents a valuable resource for the establishment of goat male reproductive stem cells lines, induction of germ cell differentiation in vitro, and the exploration of sequential cell fate transition for spermatogenesis and testicular development at single-cell resolution.

Panoramic comparison between NK cells in healthy and cancerous liver through single-cell RNA sequencing.

Objective:NK cells play crucial roles in the immune defense mechanisms against viral infections and transformed cells. However, the developmental progression, transcriptomic landscape, and functional subtypes of liver NK cells are not well defined. Hepatocellular carcinoma (HCC) accounts for approximately 80% of primary liver cancer worldwide, yet the biological characteristics of NK cells in the HCC environment are unclear. Therefore, we aimed to determine these cells’ roles in tumorigenesis and prognosis.Methods:We compared the single-cell RNA sequencing profiles of NK cells purified from blood (n = 1), healthy liver tissues (n = 3), HCC tumor tissues (n = 4), and peritumor liver tissues (n = 1) to identify NK cell subsets. Furthermore, we performed bioinformatics analysis by using The Cancer Genome Atlas (TCGA) data to identify prognostic biomarkers simultaneously overexpressed in the blood and tumor tissues of patients with HCC.Results:Transcriptomic analysis revealed 5 NK cell subsets (L1-NK-CD56bright, L2-NK-CD56dim, L3-NK-HLA, L4-LrNK-FCGR3A, and L5-LrNK-XCL1) in the healthy liver tissues. However, the transitional L3 subset and the CXCR6+CD16+ L4 subset with strong anti-tumor activity were absent in the HCC and peritumor liver tissues. Furthermore, 4 common prognosis-associated genes (RHOB, TALDO1, HLA-DPA1, and TKT) were significantly overexpressed in the paired tumor tissue and blood.Conclusions:Our study revealed 5 specific subsets of NK cells in healthy human liver tissues. However, only 3 of the 5 NK cell subsets were present in HCC and peritumor tissues. The cytotoxic NK cell subsets were absent in HCC tissues. Furthermore, we identified 4 potential non-invasive prognostic biomarkers in patients with HCC.

Real age prediction from the transcriptome with RAPToR.

Transcriptomic data is often affected by uncontrolled variation among samples that can obscure and confound the effects of interest. This variation is frequently due to unintended differences in developmental stages between samples. The transcriptome itself can be used to estimate developmental progression, but existing methods require many samples and do not estimate a specimen's real age. Here we present real-age prediction from transcriptome staging on reference (RAPToR), a computational method that precisely estimates the real age of a sample from its transcriptome, exploiting existing time-series data as reference. RAPToR works with whole animal, dissected tissue and single-cell data for the most common animal models, humans and even for non-model organisms lacking reference data. We show that RAPToR can be used to remove age as a confounding factor and allow recovery of a signal of interest in differential expression analysis. RAPToR will be especially useful in large-scale single-organism profiling because it eliminates the need for accurate staging or synchronisation before profiling.

Mathematics Learning from Concrete to Abstract (1968-2021): A Bibliometric Analysis

Mathematics learning is illustrated as a developmental progression in the direction of concrete-to-abstract by educational theorists. Various studies rooted in this notion were conducted in the past. This study aimed to profile the landscape of research rooted in this notion which was published from 1968 to 2021. The bibliographic data of 425 related publications were retrieved from the Scopus database for bibliometric analysis. Descriptive analysis and regression analysis were performed to profile the publication trend. Then, author bibliographic coupling analysis was carried out to identify the domains of research related to mathematics learning from concrete to abstract. The findings show an increasing trend of publication following the exponential model. The research was clustered into five research domains: (i) ‘manipulatives and arithmetic learning’; (ii) ‘mathematics learning of students with learning disabilities’; (iii) ‘Concrete-Representational-Abstract sequence in elementary mathematics teaching’; (iv) ‘Ideal mathematics teaching’; and (v) ‘mathematics problem-solving and mathematics learning of students with autism spectrum disorder’. The two emergent research domains in this research area are (i) ‘mathematics learning of students with learning disabilities’; and (ii) ‘mathematics problem-solving and mathematics learning of students with autism spectrum disorder’, which have the highest proportion of publications since 2015. The findings of this study can help researchers to understand the current landscape of research with the notion of mathematics learning from concrete to abstract, and hence propose pathways for future research.

Preovulatory follicle contributions to oocyte competence in cattle: importance of the ever-evolving intrafollicular environment leading up to the luteinizing hormone surge.

The preovulatory intrafollicular environment plays a major role in determining oocyte competence. The basis of this review is to highlight the importance of the preovulatory follicle's physiological status prior to the preovulatory luteinizing hormone (LH) surge and onset of oocyte maturation to promote an optimal follicular microenvironment and optimal oocyte developmental competence in cattle. While the underlying mechanisms remain unclear, and are likely multifactorial, the preovulatory follicle's physiological status prior to the preovulatory LH surge is highly influential on the oocyte's capacity to undergo postfertilization embryo development. Changes in the intrafollicular environment of the preovulatory follicle including steroid hormone production, metabolome profiles, and proteome profiles likely support the oocyte's developmental and metabolic competency. This review focuses on the relationship between bovine oocyte developmental competency and antral follicle progression to the preovulatory phase, the role of the preovulatory follicle in improving oocyte developmental competence in cattle, and the importance of the ever-evolving preovulatory intrafollicular environment for optimal fertility.

O-236 A multi-omics genome-plus-transcriptome single-cell atlas of human pre-implantation development reveals the impact of chromosome instability on cell function within the embryo

Abstract Study question Which are the transcriptional signatures of chromosome instability (CIN) on the human pre-implantation embryo biology at single-cell level? Summary answer CIN-perturbed cells show gene expression dosage effects as well as signatures of developmental delay and cell competition within the developing human embryo. What is known already According to studies analysing whole human embryos at single-cell resolution, as much as 90% of the Day3-4 and up to 100% of the Day6-12 carry one or more cells with mitotic abnormalities. Intriguingly, embryonic CIN does not necessarily preclude normal offspring, since ∼30% of mosaic blastocysts detected by preimplantation genetic testing for aneuploidy (PGT-A) can result in healthy live births. A model of post-implantation human development revealed cell selection mechanisms that deplete aneuploid cells from the germ layers. However, single-cell multi-omics approaches have not yet been applied to resolve the transcriptional signatures of CIN in human embryos. Study design, size, duration Cryopreserved human embryos donated for research were dissociated into single cells between Day1-7 post-fertilization. Cells were processed by scG&T-seq generating 295 genomes and 576 transcriptomes. This data was integrated with published single-cell RNA-seq data, totalling 2105 single-cell transcriptomes from 172 embryos. Inference of cells' DNA copy number (CN) from gene expression was benchmarked using G&T-seq data and used for cells lacking DNA-seq data. Participants/materials, setting, methods Effects of aneuploidies on gene expression, regulatory programs, lineage specification and developmental progression rates were studied by integrative analysis on single-cell whole genome copy number and whole transcriptome data. Main results and the role of chance On the genomic level, we observed frequent acquired numerical and structural chromosomal aberrations. Deletions were more frequent than duplications and were equally spread across pre-implantation stages and cell lineages. Although 88% of the embryos contained aneuploid cells, 63% still contained euploid cells. On the transcriptome level, we disclosed 248 active transcription factors (TFs), including key regulators of cell identity, that constitute 10 major gene regulatory modules driving pre-implantation development. By integrating single-cell DNA-plus-RNA information, we unveil that changes in genes’ CN directly result in transcriptional changes in the same direction, and we disclose aberrant gene regulation. Moreover, we observed cell competition instigating well before ICM/TE cell lineages specification. Common transcriptomic signatures within CIN-perturbed cells were identified. Interestingly, in TE, cell competition signatures co-existed with up-regulation of pro-proliferative and implantation-related genes. Limitations, reasons for caution Our study is based on single-cell whole genome expression data from disaggregated IVF pre-implantation embryos. Wider implications of the findings Our analyses suggest that while unfit CIN-perturbed cells might be eliminated by cell competition mechanisms, these might be tolerated and potentially beneficial in TE. Thus, encouraging the transfer of mosaic embryos after PGT-A. Besides, we provide a unique comprehensive data resource for future work. Trial registration number not applicable

PharmacoGenetic targeting of a C. elegans essential neuron provides an in vivo screening for novel modulators of nematode ion channel function

Chemical or drug treatments are successfully used to treat parasitic nematode infections that impact human, animal and plant health. Many of these exert their effects through modifying neural function underpinning behaviours essential for parasite viability. Selectivity against the parasite may be achieved through distinct pharmacological properties of the parasite nervous system, as exemplified by the success of the ivermectin which target a glutamate-gated chloride channel found only in invertebrates. Despite the success of the ivermectins, emerging resistance and concerns around eco-toxicity are driving the search for new nematocidal chemicals or drugs. Here, we describe the potential of a 5-HT-gated chloride channel MOD-1, which is involved in vital parasite behaviours with constrained distribution in the invertebrate phyla. This ion channel has potential pharmacophores that could be targeted by new nematocidal chemicals and drugs. We have developed a microtiter based bioassay for MOD-1 pharmacology based on its ectopic expression in the Caenorhabditis elegans essential neuron M4. We have termed this technology ‘PhaGeM4’ for ‘Pharmacogenetic targeting of M4 neuron’. Exposure of transgenic worms harbouring ectopically expressed MOD-1 to 5-HT results in developmental arrest. By additional expression of a fluorescence marker in body wall muscle to monitor growth we demonstrate that this assay is suitable for the identification of receptor agonists and antagonists. Indeed, the developmental progression is a robustly quantifiable bioassay that resolves MOD-1 activation by quipazine, 5-carboxyamidotryptamine and fluoxetine and highlight methiothepin as a potent antagonist. This assay has the intrinsic ability to highlight compounds with optimal bioavailability and furthermore to filter out off-target effects. It can be extended to the investigation of other classes of membrane receptors and modulators of neuronal excitation. This approach based on heterologous modulation of the essential M4 neuron function offers a route to discover new effective and selective anthelmintics potentially less confounded by disruptive environmental impact.

Comparative Proteome and Cis-Regulatory Element Analysis Reveals Specific Molecular Pathways Conserved in Dog and Human Brains.

Brain development and function are governed by precisely regulated protein expressions in different regions. To date, multiregional brain proteomes have been systematically analyzed only for adult human and mouse brains. To understand the underpinnings of brain development and function, we generated proteomes from six regions of the postnatal brain at three developmental stages of domestic dogs (Canis familiaris), which are special among animals in terms of their remarkable human-like social cognitive abilities. Quantitative analysis of the spatiotemporal proteomes identified region-enriched synapse types at different developmental stages and differential myelination progression in different brain regions. Through integrative analysis of inter-regional expression patterns of orthologous proteins and genome-wide cis-regulatory element frequencies, we found that proteins related with myelination and hippocampus were highly correlated between dog and human but not between mouse and human, although mouse is phylogenetically closer to human. Moreover, the global expression patterns of neurodegenerative disease and autism spectrum disorder–associated proteins in dog brain more resemble human brain than in mouse brain. The high similarity of myelination and hippocampus-related pathways in dog and human at both proteomic and genetic levels may contribute to their shared social cognitive abilities. The inter-regional expression patterns of disease-associated proteins in the brain of different species provide important information to guide mechanistic and translational study using appropriate animal models.

Longitudinal associations between executive functions and metacognitive monitoring in 5- to 8-year-olds

Pronounced developmental progression during the transition to formal schooling can be found in executive functions (EF) and metacognition (MC). However, it is still unclear whether and how EF and MC influence each other during this transition. Previous research with young children suggests that inhibition may be a prerequisite for monitoring skills. Thus, the present longitudinal study investigated the association between the common subcomponents of EF (inhibition, working memory, and shifting) assessed in kindergarten (T1) and metacognitive monitoring assessed in 2nd grade (T2) in a sample of N = 84 children. In line with our hypothesis, the results revealed a significant link only between the EF subcomponent inhibition and later metacognitive monitoring. More precisely, children with better inhibition skills in kindergarten showed less overconfident monitoring in elementary school. Interestingly, the longitudinal relationship between inhibition and monitoring was not bidirectional. The findings indicate an essential role of early inhibition skills regarding emerging and developing elementary school children’s monitoring skills.

Using newly optimized genetic tools to probe Strongyloides sensory behaviors

The oft-neglected human-parasitic threadworm, Strongyloides stercoralis, infects roughly eight percent of the global population, placing disproportionate medical and economic burden upon marginalized communities. While current chemotherapies treat strongyloidiasis, disease recrudescence and the looming threat of anthelminthic resistance necessitate novel strategies for nematode control. Throughout its life cycle, S. stercoralis relies upon sensory cues to aid in environmental navigation and coordinate developmental progression. Odorants, tastants, gases, and temperature have been shown to shape parasite behaviors that drive host seeking and infectivity; however, many of these sensory behaviors remain poorly understood, and their underlying molecular and neural mechanisms are largely uncharacterized. Disruption of sensory circuits essential to parasitism presents a promising strategy for future interventions. In this review, we describe our current understanding of sensory behaviors – namely olfactory, gustatory, gas sensing, and thermosensory behaviors – in Strongyloides spp. We also highlight the ever-growing cache of genetic tools optimized for use in Strongyloides that have facilitated these findings, including transgenesis, CRISPR/Cas9-mediated mutagenesis, RNAi, chemogenetic neuronal silencing, and the use of fluorescent biosensors to measure neuronal activity. Bolstered by these tools, we are poised to enter an era of rapid discovery in Strongyloides sensory neurobiology, which has the potential to shape pioneering advances in the prevention and treatment of strongyloidiasis.

Children's self and other's body perception: Effects of familiarity and gender on how children perceive adults.

Our ability to perceive our own and other people's bodies is critical to the success of social interactions. Research has shown that adults have a distorted perception of their own body and those of other adults. However, these studies ask perceivers to estimate for adults with a similar bodily make-up. This study explored the developmental progression in how children perceive their own body (6- to 12-year-old children; from a predominantly White urban population of middle socioeconomic status; E1) and whether children have similar distortions as adults when estimating the dimensions of adults' bodies both unknown (E2) and familiar to them (E3). Overall, children showed similar distortions to those found in adult's estimations for own body perception (i.e., limbs with a smaller density of sensory receptors showed a larger error than those with a higher density). Perception of adults' bodies showed less distortion when perceiver and model were of the same gender, but not when the adult was familiar to the child. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Phenological piecewise modelling is more conducive than whole-season modelling to winter wheat yield estimation based on remote sensing data

ABSTRACT Most of the existing remote sensing-based yield estimation methods adopt the mean or cumulative value of meteorological factors within the whole growing season, which may ignore the impact of adverse meteorological conditions on the growth of winter wheat in a certain phenological period. In this study, we distinguished the developmental progression of winter wheat as three phenological periods. In each phenological period, the vegetation indices and meteorological factors were optimized. Then the accuracy and spatiotemporal transferability of the phenological piecewise modelling was compared with that of the whole-season modelling based on four regression methods (i.e. multiple linear regression, artificial neural network, support vector regression and random forest). The results showed that the optimal combinations of variables for the whole-season modelling and the phenological piecewise modelling were different. Compared with the whole-season models, the R2 for the phenological piecewise models improved by 1.4% to 7.6%, the root mean square error (RMSE) decreased by 1.1% to 8.2% among four regression methods . In addition, compared with the whole-season models, the spatiotemporal transferability for the phenological piecewise models was generally better. The accuracies after spatiotemporal transfer for the phenological piecewise models were still higher than that for the whole-season models.

Gaze and social functioning associations in autism spectrum disorder: A systematic review and meta-analysis.

Autism spectrum disorder (ASD) is characterized by significant social functioning impairments, including (but not limited to) emotion recognition, mentalizing, and joint attention. Despite extensive investigation into the correlates of social functioning in ASD, only recently has there been focus on the role of low‐level sensory input, particularly visual processing. Extensive gaze deficits have been described in ASD, from basic saccadic function through to social attention and the processing of complex biological motion. Given that social functioning often relies on accurately processing visual information, inefficient visual processing may contribute to the emergence and sustainment of social functioning difficulties in ASD. To explore the association between measures of gaze and social functioning in ASD, a systematic review and meta‐analysis was conducted. A total of 95 studies were identified from a search of CINAHL Plus, Embase, OVID Medline, and psycINFO databases in July 2021. Findings support associations between increased gaze to the face/head and eye regions with improved social functioning and reduced autism symptom severity. However, gaze allocation to the mouth appears dependent on social and emotional content of scenes and the cognitive profile of participants. This review supports the investigation of gaze variables as potential biomarkers of ASD, although future longitudinal studies are required to investigate the developmental progression of this relationship and to explore the influence of heterogeneity in ASD clinical characteristics.Lay SummaryThis review explored how eye gaze (e.g., where a person looks when watching a movie) is associated with social functioning in autism spectrum disorder (ASD). We found evidence that better social functioning in ASD was associated with increased eye gaze toward faces/head and eye regions. Individual characteristics (e.g., intelligence) and the complexity of the social scene also influenced eye gaze. Future research including large longitudinal studies and studies investigating the influence of differing presentations of ASD are recommended.

Assessment of Executive Function in Infants and Toddlers: A Potential Role of the Bayley-4.

The development of executive function (EF) in infants and toddlers has received increased interest by clinicians and researchers. Higher rates of deficits in EF have been reported in at-risk groups of infants such as those born extremely preterm. These deficits play an important role in the etiology of early neurodevelopmental problems and are predictive of subsequent nonoptimal educational outcomes. In this study, the Bayley-4 is used to follow the developmental course of EF and to determine whether EF is a unitary concept or can be parsed into discrete components over the first 42 months. All 81 cognitive items from the Bayley-4 normative sample of 1700 infants and toddlers were classified a priori into 6 EFs, and then, 5 age groups derived from Bayley-4 start points were factor analyzed to determine at what age EFs emerge and to address the controversy of whether the factor structure of the cognitive items for each of 5 age groups reflect a single factor or multiple factors. Bayley-4 items form 1 to 5 EF factors for each age group, accounting for 59% to 74% of the variance. There is a developmental progression in EF as well. The results indicate EF constructs can be identified early. Executive function tasks in infants and toddlers are interrelated with task content either remaining the same or changing with advancing age (i.e., content that is homotypic or heterotypic, respectively). EFs measured by Bayley-4 items are useful clinically and become more complex with increasing age, corresponding to more advanced brain development and integration. The findings have the potential of providing additional information in the assessment of infants at risk such as those born preterm.

Physical literacy predicts the physical activity and sedentary behaviours of youth

ObjectivesThis study examined the physical activity (PA) and sedentary behaviour (SB) along with the developmental progression of 2,087 Canadian students. It also examined whether their physical literacy (PL) predicts latent class affiliations and transition probabilities from grades 5 to 6 and whether this affiliation in grade 6 predicts body mass index (BMI) and self-concept by grade 7. DesignLongitudinal observational study. MethodsData was collected from a longitudinal open cohort study using data from three waves of data. In grades 5 and 6 we examined patterns of PA and SB behaviour and their correlates. In grade 7 we examined outcomes associated with latent class affiliation. ResultsOur results found a validated measure of PL was a robust predictor of class affiliation and transitions between classes across grade and sex. Students with higher PL were two to four times more likely to be in the active screeners (AS) or low SB class compared to the sedentary/inactive (SI) class in both grades 5 and 6. For females, PL was also related to transitioning out of the SI class and into the AS. PL did not predict transitions out of the low SB class. Class affiliation in grade 6 also predicted BMI and self-concept in grade 7. Students in the SI class had higher BMI and lower self-concept compared to students in AS and low SB classes. ConclusionsFuture research should assess additional domains of PL and utilize objective methods to measure PA.

Helix-Loop-Helix Proteins in Adaptive Immune Development.

The E/ID protein axis is instrumental for defining the developmental progression and functions of hematopoietic cells. The E proteins are dimeric transcription factors that activate gene expression programs and coordinate changes in chromatin organization. Id proteins are antagonists of E protein activity. Relative levels of E/Id proteins are modulated throughout hematopoietic development to enable the progression of hematopoietic stem cells into multiple adaptive and innate immune lineages including natural killer cells, B cells and T cells. In early progenitors, the E proteins promote commitment to the T and B cell lineages by orchestrating lineage specific programs of gene expression and regulating VDJ recombination of antigen receptor loci. In mature B cells, the E/Id protein axis functions to promote class switch recombination and somatic hypermutation. E protein activity further regulates differentiation into distinct CD4+ and CD8+ T cells subsets and instructs mature T cell immune responses. In this review, we discuss how the E/Id proteins define the adaptive immune system lineages, focusing on their role in directing developmental gene programs.