Functional Evolution Research Articles

How Can an Urban Botanical Garden in a Densely Built-Up Landscape Develop Sustainably with Urban Renewal?—The Case of Shanghai Botanical Garden

Urban botanical gardens collect, preserve, research, and utilize important regional plant resources and serve as ecologically friendly cores of development and renewal for urban organisms. Meanwhile, they offer garden landscape displays and public science education. Furthermore, biodiversity conservation has become important globally. Here, the connotation of urban botanical gardens is interpreted, the functional evolution of urban botanical gardens is examined, and the challenges of sustainably developing urban botanical gardens in the context of biodiversity conservation are analysed. Taking the Shanghai Botanical Garden as an example, the abilities of urban botanical gardens in high-density downtown areas to coexist with urban spaces and thrive along with cities—thus enhancing their five core functions of ex situ conservation, scientific research, popular science education, garden horticulture, and public service—are discussed. These discussions provide references for the sustainable development of urban botanical gardens in similarly high-density city centres.

Corrigendum: Camel proteins and enzymes: a growing resource for functional evolution and environmental adaptation

Corrigendum: Camel proteins and enzymes: a growing resource for functional evolution and environmental adaptation

Evolution of light-dependent functions of GIGANTEA.

GIGANTEA is a multifaceted plant-specific protein that originated in a streptophyte ancestor. The current known functions of GI include circadian clock control, light signalling, flowering time regulation, stomata response, chloroplast biogenesis, accumulation of anthocyanin, chlorophyll, and starch, phytohormone signalling, senescence and response to drought, salt, and oxidative stress. Six decades since its discovery, no functional domains have been defined, and its mechanism of action is still not well-characterised. In this review, we explore the functional evolution of GI to distinguish between ancestral and more recently acquired roles. GI integrated itself into various existing signalling pathways of the circadian clock, blue light, photoperiod, and osmotic and oxidative stress response. It also evolved parallelly to acquire new functions for chloroplast accumulation, red light signalling and anthocyanin production. In this review, we have encapsulated the known mechanisms of various biological functions of GI. Additionally, this manuscript will throw light on the evolution of GI in plant lineage.

Tissue-specific, temporal, and core gene-dependent expression patterns of Hsp70s reveal functional allocation in Chlamys farreri under heat stress

Heat shock proteins 70 KDa (Hsp70s) engage in a broad spectrum of cellular functions in response to various stressors. Marine bivalves face substantial threats from the rising seawater temperature attributed to global warming. In the present study, expression patterns of Hsp70s in Zhikong scallop Chlamys farreri (CfHsp70s) were determined in embryos and larvae at all developmental stages, in healthy adult tissues, and across four various tissues exposed to high temperature for acute and chronic periods through in silico analysis. Spatiotemporal expressions suggested CfHsp70s performed specific functional differentiations in scallop's development and growth. Regulatory expression patterns of CfHsp70s, characterized by predominant down-regulation in the mantle, gill and hemocytes, as well as contrasting up-regulation in the heart, suggest differential functional allocation of CfHsp70s among tissues in response to heat stress. Particularly, a core set of 14 CfHsp70s, especially the nine members of the Hsp70B2s, characterized by gene expansion, intron-less structure, shorter gene length, preference for hydrophilic amino acids, and coordinated expression profiles, was predominantly responsible for the inducible up-regulations observed across all four tissue types. Collectively, the tissue-specific, temporal and core gene-dependent expression patterns of CfHsp70s illustrate the functional allocation and molecular evolution of Hsp70 family members in Zhikong scallops.

Arrangements of intramembranous muscles of wings are influenced by body mass across the radiation of phyllostomid bats.

Extensive research into bat flight mechanisms has highlighted the complex functional and evolutionary dynamics of their wing structures, yet the anatomical details of certain wing muscles remain elusive. In particular, the intramembranous plagiopatagiales proprii muscles, located within the plagiopatagium-an area of the wing lacking direct joint connections-exhibit remarkable variation across bat families. These muscles, which extend anteroposteriorly in macroscopic bundles, play a crucial role in wing stiffening, modulating membrane tension, and reducing wing curvature during flight. Since larger bats tend to have higher wing loading (WL; the ratio of body mass [BMa] to wing area) and may therefore experience increased patagial curvature and resultant drag, we hypothesized that body size significantly influences the evolutionary development of the plagiopatagiales proprii muscles. This study investigates the relationship between BMa and the morphology of the plagiopatagiales proprii in New World leaf-nosed bats (Phyllostomidae), employing bivariate allometry, multivariate analysis, and comparative phylogenetic methods across 24 species from eight phyllostomid subfamilies. Our findings reveal a significant phylogenetic signal in muscle architecture, along with positive evolutionary allometry in muscle area. This suggests an adaptive increase in muscle size in larger species, likely to counterbalance the increased WL, reduce wing curvature, and minimize drag. This research enhances our understanding of the functional and adaptive morphological evolution of intramembranous wing muscles in phyllostomid bats, underscoring their evolutionary significance.

Experimental and Theoretical Study on Surface Reactivity and CO Generation Mechanism of Bituminous Coal during Room-Temperature Oxidation.

To investigate the evolution of the microscopic chemical structure during the oxidation of bituminous coal at room temperature (25 °C) and infer the formation mechanism of carbon monoxide (CO), a self-designed closed-system coal oxidation experimental setup was employed to measure the CO generation from three bituminous coal samples [Duanwang (DW), Linsheng (LS), and Kunning (KN)]. 13C nuclear magnetic resonance and X-ray photoelectron spectroscopy were used to determine the structures and contents of different carbon atoms and surface elemental compositions and chemical states of the coal samples. Molecular models were constructed on the basis of the experimental data, and reactive force field pyrolysis simulation was used to trace the carbon atoms in the generated CO molecules. In combination with the results of interactive Mantel correlation analysis on the Fourier transform infrared experimental data of coal samples oxidized at room temperature for 0, 12, 24, 36, 48, and 60 h, the main functional groups, structures, and evolution of coal involved in CO formation during normal temperature oxidation were determined. The constructed molecular formulas for the coal samples were C154H122O28N2S for DW, C145H114O16N2S2 for LS, and C155H92O16N2S for KN. The formation of CO was related to the transformation of carbonyl (C═O), phenolic hydroxyl (-OH), ether (C-O-C), aromatic, and aliphatic structures in the coal.

Functional evolution of island dwellings in Dongshan Island, Fujian, under the influence of socio-cultural factors

ABSTRACT Unique natural conditions and socio-cultural backgrounds influenced the evolution of island dwellings, a type of dwellings in China. Over time, the influence of socio-cultural factors, particularly on architectural functions, has gradually become prominent. This study takes Tongshan Ancient City in Dongshan County, Fujian Province, as an example to study the changes in function and socio-cultural factors, and clarify this mechanism. It investigates 52 dwellings, and summarizes the evolution of architectural functions. By analyzing two clues of changes, this study determined three main socio-cultural factors with the most influence: transformation of industrial structure, change of personnel composition, and continuity of religious beliefs.

Juvenile hormone signaling is indispensable for late embryogenesis in ametabolous and hemimetabolous insects

BackgroundJuvenile hormone (JH) is an insect-exclusive hormone involved in regulating diverse aspects of insect physiology, and the evolution of its diverse function is widely interesting. Studying embryogenesis in basal wingless insects is important to understand the functional evolution of JH; however, experimental studies in this regard are scarce. In this study, we conducted CRISPR/Cas9-mediated knockout (KO) of genes involved in JH biosynthesis and signaling cascades in the ametabolous firebrat, Thermobia domestica. Additionally, we investigated whether the primitive action of JH is conserved in the hemimetabolous cricket, Gryllus bimaculatus.ResultsWe observed that KO of JHAMT, CYP15A1, Met, and Kr-h1 resulted in embryonic lethality in T. domestica. Deprivation of JH or JH signaling arrested the progression of extraembryonic fluid resorption after dorsal closure and hatching, which is consistent with the gene expression pattern showing high Kr-h1 expression in the late embryos of T. domestica. The embryos deficient in JH signaling displayed wrinkled and weak legs. Comparative transcriptome analysis revealed that JH signaling promotes embryonic leg maturation through inducing energy supply and muscle activity, as validated by transmission electron microscopy (TEM). In addition, JH signaling exhibited similar embryonic effects in G. bimaculatus.ConclusionsThis study reveals the indispensable role of JH signaling in facilitating the maturation of terminal tissues during late embryogenesis, as demonstrated by the regulation of leg development, in ametabolous and hemimetabolous insects. These findings further indicate that the embryonic functions of JH evolved earlier than its anti-metamorphic functions during postembryonic development.

Genomic Analysis and Expression Dynamics of GH3 Genes Under Abiotic Stresses in Brassica rapa

ABSTRACTIn silico characterization of the Gretchen Hagen3 (GH3) gene family is required for understanding phytohormone regulation and stress responses in Brassica rapa to develop the improved stress‐tolerant cultivars. The main objective of this research was to identify the key BrGH3 genes under different abiotic stresses. Using bioinformatics tools, a total of 27 BrGH3 genes were identified in B. rapa for which phylogenetic relationship, syntenic pairing, conserved motifs, miRNA regulation, and cis‐regulatory elements of BrGH3s were also studied. BrGH3 gene expression has been examined in numerous tissues and under various abiotic and phytohormone stressors. Phylogenetic studies separated BrGH3 genes into three major classes and nine subclasses based on gene functional evolution. Collinearity analysis demonstrated that all BrGH3 genes had syntenic linkage with AtGH3, BnaGH3, and BolGH3, indicating that genome duplication mechanisms were crucial to BrGH3 gene evolution. The expression dynamics of BrGH3 under diverse phytohormonal stresses methyl jasmonate (MeJA), auxin (IAA), abscisic acid (ABA), gibberellic acid (GA), and salicylic acid (SA) at different time intervals suggest that BrGH3‐5.1 has a consistently greater expression than other BrGH3 genes. Under salt, drought, and low temperature stress, BrGH3‐1 and BrGH3‐4 genes expressed comparatively higher. The findings suggest that five genes (BrGH3‐5.1, BrGH3‐5.2, BrGH3‐15, BrGH3‐17.2, and BrGH3‐19) have a key role in inducing broad stress resilience. These results can be beneficial in developing stress‐tolerant varieties of Chinese cabbage.

A classic key innovation constrains oral jaw functional diversification in fishes

Abstract Modifications to the pharyngeal jaws—a prey processing system located posterior to the mouth cavity—are widely considered a key innovation that enhanced diversification within several prominent fish clades. Seen in cichlids, damselfishes, wrasses, and a few other lineages, these musculoskeletal alterations are believed to increase the evolutionary independence and, thus, the diversification of the oral and pharyngeal jaw systems. To test this classic hypothesis, we conducted comparative phylogenetic analyses to assess the effect of the pharyngeal novelty on the diversification of feeding morphology and kinematics across a taxonomically diverse sample of spiny-rayed fishes. We quantified movements of the oral jaws and other craniofacial structures from 689 suction-feeding strikes using high-speed videos collected from 228 species with and without the pharyngeal jaw novelty. Contradicting long-held predictions, we find significantly greater disparity across all traits and faster rates of oral jaw functional evolution in fishes without the specialized prey processing system. The modified pharyngeal jaw is undoubtedly a functional innovation as it enhances the strength of the prey processing system, facilitating exceptional transition rates to feeding on hard and tough prey. However, it also restricts the diversification of the feeding system, revealing that the impact of pharyngognathy is more nuanced than previously thought. In light of these and other recent findings, a reinterpretation of the macroevolutionary consequences of the pharyngeal jaw novelty is needed.

Chromosome genome assembly and annotation of Adzuki Bean (Vigna angularis)

Adzuki bean (Vigna angularis) is a significant dietary legume crop that is prevalent in East Asia. It also holds traditional medicinal importance in China. In this study, we report a high-quality, chromosome-level genome assembly of adzuki bean obtained by employing Illumina short-read sequencing, PacBio long-read sequencing, and Hi-C technology. The assembly spans 447.8 Mb, encompassing 96.32% of the estimated genome, with contig and scaffold N50 values of 16.5 and 41.0 Mb, respectively. More than 98.2% of the 1,614 BUSCO genes were fully identified, and 25,939 genes were annotated, with 98.23% of them being functionally identifiable. Vigna angularis was estimated to diverge successively from Vigna unguiculata and Vigna radiata about 15.3 and 8.7 million years ago (Ma), respectively. This chromosome-level reference genome of Vigna angularis provides a robust foundation for exploring the functional genomics and genome evolution of adzuki bean, thereby facilitating advancements in molecular breeding of adzuki bean.

Long head of biceps tendon augmentation in rotator cuff repair enhances tendon healing, shoulder function and patient-reported outcomes one-year post-surgery.

The aim is to determine the effect on healing and functionality of patients after 1 year of biceps augmentation of a rotator cuff repair (RCR) compared to RCR plus long head of the biceps (LHB) tenotomy. In addition, to analyse the main factors involved in the recovery after the surgery. A prospective, comparative, non-randomized study (Level of Evidence III) was conducted. Patients with repairable rotator cuff tears were allocated to either the control group, with a double row transosseous equivalent RCR with LHB tenotomy, or the RCR+augmentation with LHB group. Patients were evaluated for radiological (MRI), clinical (cuff size, Patte and Goutallier scales) and functional variables (Constant and American Shoulder and Elbow Surgeons [ASES] scales) before the intervention. At 1-year follow-up cuff healing was confirmed through MRI and functional evaluation with Constant, ASES, simple shoulder test [SST] and Disabilities of the Arm, Shoulder and Hand scales. Seventy-seven patients underwent control or RCR+augmentation with LHB, there were no preoperative differences between the groups. After 1 year of the surgery, re-rupture occurred in 38.5% and 16% of the patients in control and RCR+augmentation with LHB groups, respectively (p = .026). Total functionality was higher (p < .05) in RCR+augmentation with LHB than in the control group: Constant, SST and ASES scales. Among the explored factors involved in healing, re-rupture occurred in 100% of the cases with high fatty degeneration. Besides, higher initial functionality (Constant scale) and RCR+augmentation with LHB increased the odds of healing (odds ratio [OR] = 1.12 [1.04-1.21]; OR = 5 [1, 61], respectively), while higher cuff length had a detrimental effect (OR = 0.92 [0.85-0.99]). RCR+augmentation with LHB achieves a higher healing percentage and a better functional evolution than RCR+LHB tenotomy, 1 year after cuff repair. Fatty degeneration, cuff length and initial functionality are the main factors involved in cuff healing. Level III randomized controlled trial.

Geography and ecology structure diversification in Ziziphus Mill. (Rhamnaceae)

Understanding the processes responsible for creating and preserving biodiversity within tropical ecosystems is essential for gaining deeper insights into the history, dynamics, and resilience of these environments. We investigated the biogeography and evolution of Ziziphus Mill. (Rhamnaceae), a genus of c.50 species found in all major tropical biomes and across Africa, Asia and Australasia to evaluate how ecology and geography structures its diversification, and their associations with functional traits. We used consistency and retention indices, as well as the delta statistic to test for phylogenetic signal in ecology, geography and functional traits. We constructed a time-calibrated phylogeny using BEAST, followed by the reconstruction of biome and geographical affinities in BioGeoBEARS, and ancestral functional trait evolution using phytools and ape. At a global scale, geography structures Ziziphus’ diversification more than ecology, as evidenced by higher phylogenetic signal in retention indices and the delta statistic. Multiple ecological switches among biomes are associated with dispersal events, which structure Ziziphus’ diversification at smaller scales. Biogeographic estimation suggests that Ziziphus evolved out of closed biomes in Asia during the Oligocene. Long distance dispersal from Asia to Africa resulted in the occupation of two novel biomes, the expanding tropical grassy biome and the desertic biome. Geographic transitions across continents that retain the same biome are fewer but are demonstrated by a dispersal from the closed biome in Asia to the same ecological setting in Australia. In keeping with the younger age of the savanna biome and the Pliocene radiation of geoxylic species, the youngest species in Ziziphus are mostly found in open biomes, and the youngest habit is geoxylic. Leaf hair appears to confer advantages across biomes whilst being a synapomorphy for open and desertic clades. One of two evolutions back into closed biomes is associated with the development of the liana habit. We inferred the most complete phylogeny for Ziziphus to date. Ziziphus originated in closed biomes in Asia in the Oligocene. At a global scale, geography structures diversification more than ecology (biome preference) in Ziziphus. Biome shifts are frequently associated with long distance dispersal events. Shifts in growth form are frequently associated with biome shifts.

Cancerous time estimation for interpreting the evolution of lung adenocarcinoma.

The evolution of lung adenocarcinoma is accompanied by a multitude of gene mutations and dysfunctions, rendering its phenotypic state and evolutionary direction highly complex. To interpret the evolution of lung adenocarcinoma, various methods have been developed to elucidate the molecular pathogenesis and functional evolution processes. However, most of these methods are constrained by the absence of cancerous temporal information, and the challenges of heterogeneous characteristics. To handle these problems, in this study, a patient quasi-potential landscape method was proposed to estimate the cancerous time of phenotypic states' emergence during the evolutionary process. Subsequently, a total of 39 different oncogenetic paths were identified based on cancerous time and mutations, reflecting the molecular pathogenesis of the evolutionary process of lung adenocarcinoma. To interpret the evolution patterns of lung adenocarcinoma, three oncogenetic graphs were obtained as the common evolutionary patterns by merging the oncogenetic paths. Moreover, patients were evenly re-divided into early, middle, and late evolutionary stages according to cancerous time, and a feasible framework was developed to construct the functional evolution network of lung adenocarcinoma. A total of six significant functional evolution processes were identified from the functional evolution network based on the pathway enrichment analysis, which plays critical roles in understanding the development of lung adenocarcinoma.

Bursts of Rapid Diversification, Dispersals Out of Southern Africa, and Two Origins of Dioecy Punctuate the Evolution of Asparagus.

The genus Asparagus arose ∼9 to 15 million years ago (Ma), and transitions from hermaphroditism to dioecy (separate sexes) occurred ∼3 to 4 Ma. Roughly 27% of extant Asparagus species are dioecious, while the remaining are bisexual with monoclinous flowers. As such, Asparagus is an ideal model taxon for studying the early stages of dioecy and sex chromosome evolution in plants. Until now, however, understanding of diversification and shifts from hermaphroditism to dioecy in Asparagus has been hampered by the lack of robust species tree estimates for the genus. In this study, a genus-wide phylogenomic analysis including 1,726 nuclear loci and comprehensive species sampling supports two independent origins of dioecy in Asparagus-first in a widely distributed Eurasian clade and then in a clade restricted to the Mediterranean Basin. Modeling of ancestral biogeography indicates that both dioecy origins were associated with range expansion out of southern Africa. Our findings also reveal several bursts of diversification across the phylogeny, including an initial radiation in southern Africa that gave rise to 12 major clades in the genus, and more recent radiations that have resulted in paraphyly and polyphyly among closely related species, as expected given active speciation processes. Lastly, we report that the geographic origin of domesticated garden asparagus (Asparagus officinalis L.) was likely in western Asia near the Mediterranean Sea. The presented phylogenomic framework for Asparagus is foundational for ongoing genomic investigations of diversification and functional trait evolution in the genus and contributes to its utility for understanding the origin and early evolution of dioecy and sex chromosomes.

The Human Accelerated Region HAR202 Controls NPAS3 Expression in the Developing Forebrain Displaying Differential Enhancer Activity Between Modern and Archaic Human Sequences.

It has been proposed that the phenotypic differences in cognitive abilities between humans and our closest living relatives, chimpanzees, are largely due to changes in the regulation of neurodevelopmental genes. We have previously found that the neurodevelopmental transcription factor gene NPAS3 accumulates the largest number of human accelerated regions (HARs), suggesting it may play some role in the phenotypic evolution of the human nervous system. In this work, we performed a comparative functional analysis of NPAS3-HAR202 using enhancer reporter assays in transgenic zebrafish and mice. We found that the Homo sapiens HAR202 ortholog failed to drive reporter expression to the zebrafish nervous system, in high contrast to the strong expression displayed by the rest of the vertebrate ortholog sequences tested. Remarkably, the HAR202 ortholog from archaic humans (Neanderthals/Denisovans) also displayed a pan-vertebrate expression pattern, despite the fact that archaic and modern humans have only one nucleotide substitution. Moreover, similar results were found when comparing enhancer activity in transgenic mice, where we observed a loss of activity of the modern human version in the mouse developing brain. To investigate the functional importance of HAR202, we generated mice lacking HAR202 and found a remarkable decrease of Npas3 expression in the forebrain during development. Our results place HAR202 as one of the very few examples of a neurodevelopmental transcriptional enhancer displaying functional evolution in the brain as a result of a fast molecular evolutionary process that specifically occurred in the human lineage.

Functional evolution of facial bristle feathers in Old World passerines

Abstract Many bird species have vaneless hair-like feathers in the frontal area of the head (facial bristles). Several alternative hypotheses on the functional significance of avian facial bristles have been proposed, including aid in insect capture, eye protection, and mechanosensory sensitivity. Here, we used a phylogenetically-informed comparative approach to examine functional evolution of facial bristle feathers in Old World passerines (Passeriformes). For this purpose, we quantified the number and length of facial bristles located at the base of the upper beak (upper rictal bristles) in over 1300 birds representing 73 species and 21 families, and tested for evolutionary associations of these traits with species ecology, biogeography, life history, and morphology. We found that more numerous and longer rictal bristles have evolved in association with invertivory and omnivory. The number or length of rictal bristles was also linked to aerial foraging, foraging in low vegetation, occupancy of shrubland habitats, and migration. All these evolutionary correlations suggest that avian rictal bristles may serve multiple non-exclusive functions related to insect capture and tactile sensing. Comparisons with previous research provide support for scale dependence in avian rictal bristle evolution and decoupling of evolutionary processes at different levels of phylogenetic organization.

Deep Learning-Based Self-Adaptive Evolution of Enzymes

AbstractBiocatalysis has been widely used to prepare drug leads and intermediates. Enzymatic synthesis has advantages, mainly in terms of strict chirality and regional selectivity compared with chemical methods. However, the enzymatic properties of wild-type enzymes may or may not meet the requirements for biopharmaceutical applications. Therefore, protein engineering is required to improve their catalytic activities. Thanks to advances in algorithmic models and the accumulation of immense biological data, artificial intelligence can provide novel approaches for the functional evolution of enzymes. Deep learning has the advantage of learning functions that can predict the properties of previously unknown protein sequences. Deep learning-based computational algorithms can intelligently navigate the sequence space and reduce the screening burden during evolution. Thus, intelligent computational design combined with laboratory evolution is a powerful and potentially versatile strategy for developing enzymes with novel functions. Herein, we introduce and summarize deep-learning-assisted enzyme functional adaptive evolution strategies based on recent studies on the application of deep learning in enzyme design and evolution. Altogether, with the developments of technology and the accumulation of data for the characterization of enzyme functions, artificial intelligence may become a powerful tool for the design and evolution of intelligent enzymes in the future.

Functional evolution and diversification of CYP82D subfamily members have shaped flavonoid diversification in the genus Scutellaria

Flavonoids, the largest class of polyphenols, exhibit substantial structural and functional diversity, yet their evolutionary diversification and specialized functions remain largely unexplored. The genus Scutellaria is notable for its rich flavonoid diversity, particularly of 6/8-hydroxylated variants biosynthesized by the cytochrome P450 subfamily CYP82D. Our study analyzes metabolic differences between Scutellaria baicalensis and Scutellaria barbata, and the results suggest that CYP82Ds have acquired a broad range of catalytic functions over their evolution. By integrating analyses of metabolic networks and gene evolution across 22 Scutellaria species, we rapidly identified 261 flavonoids and delineated five clades of CYP82Ds associated with various catalytic functions. This approach revealed a unique catalytic mode for 6/8-hydroxylation of flavanone substrates and the first instance of 7-O-demethylation of flavonoid substrates catalyzed by a cytochrome P450. Ancestral sequence reconstruction and functional validation demonstrated that gradual neofunctionalization of CYP82Ds has driven the chemical diversity of flavonoids in the genus Scutellaria throughout its evolutionary history. These findings enhance our understanding of flavonoid diversity, reveal the intricate roles of CYP82Ds in Scutellaria species, and highlight the extensive catalytic versatility of cytochrome P450 members within plant taxa.

Evolution of the basic Helix-Loop-Helix transcription factor SPATULA and its role in gynoecium development.

SPATULA (SPT) encodes a basic Helix-Loop-Helix transcription factor in Arabidopsis thaliana that functions in the development of the style, stigma and replum tissues, all of which arise from the carpel margin meristem (CMM) of the gynoecium. Here, we use a comparative approach to investigate the evolutionary history of SPT and identify changes that potentially contributed to its role in gynoecium development. We investigate SPT's molecular and functional evolution using phylogenetic reconstruction, yeast-2-hybrid analyses of protein-protein interactions, microarray-based analyses of protein-DNA interactions, plant transformation assays, RNA in-situ hybridization, and in-silico analyses of promoter sequences. We demonstrate the SPT lineage to have arisen at the base of euphyllophytes from a clade of potentially light-regulated transcription factors through gene duplication followed by the loss of an Active Phytochrome Binding (APB) domain. We also clarify the more recent evolutionary history of SPT and its paralog ALCATRAZ (ALC), which appear to have arisen through a large-scale duplication within Brassicales. We find that SPT orthologs from diverse groups of seed plants share strikingly similar capacities for protein-protein and protein-DNA interactions, and that SPT coding regions from a wide taxonomic range of plants are able to complement loss-of-function spt mutations in transgenic Arabidopsis. However, the expression pattern of SPT appears to have evolved significantly within angiosperms, and we identify structural changes in SPT's promoter region that correlate with the acquisition of high expression levels in tissues arising from the CMM in Brassicaeae. We conclude that changes to SPT's expression pattern made a major contribution to the evolution of its developmental role in the gynoecium of Brassicaeae. By contrast, the main biochemical capacities of SPT, as well as many of its immediate transcriptional targets, appear to have been conserved at least since the base of living angiosperms.