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At least 19 recordsLinked to original sources
PubMed2026

A high-quality draft genome assembly of Johnsongrass illuminates relationships between polyploidization, crop-wild hybridization, and reproductive biology.

Johnsongrass [Sorghum halepense (L.) Pers.] is an allopolyploid, rhizomatous, perennial grass species and one of the most troublesome weeds in global agriculture. We assembled the first Johnsongrass genome to clarify poorly understood genetic factors influencing variable rates of crop-wild hybridization with cultivated sorghum [S. bicolor (L.) Moench]. The draft genome assembly has a total size of 3.26 Gb and BUSCO completeness of 95.3%. We also report the first evolutionary analysis of INHIBITION OF ALIEN POLLEN (IAP), the only known cross-(in)compatibility locus in the genus. Our results reveal an evolutionary history of genome instability, including the loss of distinct parental subgenomes, and suggest that Nebraska accession 'J-37,' the genome donor, is a segmental allotetraploid that may function as a diploid or aneuploid during meiosis. Genome instability could explain observations of variable ploidies in Johnsongrass and facilitate ongoing hybridization with sorghum where gamete ploidies and IAP alleles match. Given this information, we provide a suggested research framework for studying evolution and gene expression in the Sorghum genus where crop-wild hybridization occurs and for predicting the potential for hybridization between specific crossing partners. Collectively, this work will bolster efforts to study and manage reproductive biology in other crop-wild polyploid complexes.

Sorghum↗
PubMed2026

The Polish Konik Horse: A Multidisciplinary Review of Its Origin, Genetics, Ecology, Health, Behaviour and Reproductive Biology.

The Polish Konik horse (PKH) is one of Europe's best-known native conservation breeds. Traditionally associated with the extinct Eurasian tarpan and conservation grazing, the breed has recently become the subject of multidisciplinary research encompassing genetics, ecology, health, behaviour and reproduction. This narrative review summarises current knowledge on the biological characteristics and contemporary scientific significance of the PKH. Literature published between 2005 and 2026 was identified through searches of PubMed, Scopus, Web of Science and Google Scholar and narratively synthesised. Available evidence suggests that, despite severe historical bottlenecks, the PKH has retained considerable genetic diversity and its characteristic maternal and paternal founder-line structure. Recent molecular studies have revised traditional concepts of the breed's origin, while ecological research supports its important role in conservation grazing and wetland restoration. Behavioural and reproductive studies indicate stable temperament, high reproductive efficiency and adaptation to extensive management systems. However, current knowledge is derived predominantly from observational studies, with relatively few comparative investigations and limited genomic and longitudinal data. The PKH represents a valuable model for research on conservation genetics, environmental adaptation, animal welfare, reproductive biology and ecosystem management. Further interdisciplinary studies are needed to strengthen the evidence base for conservation and breeding strategies.

Polish Konik horse↗
PubMed1979

The reproductive ecology of the house mouse.

This paper attempts to integrate the physiological and ecological perspectives of the reproductive biology of the house mouse (Mus musculus). The endeavor is made within a larger context to provide a prototype for mammalian reproductive ecology in general. Specifically, the environmental regulation of the reproduction of Mus musculus is examined in relation to its ecological opportunism and, in particular, in relation to its history of global colonization. House mice can live as commensals of man or under totally feral conditions. Stable, high density, commensal populations are characterized by an insular division of the living space into demeterritories, each dominated by a single male. Feral populations typically are characterized by temporal, spatial, and social instability. Territoriality is improbable under such conditions, particularly given the necessity for large home ranges in most feral habitats. In both feral and commensal populations, however, male aggressiveness promotes the large-scale dispersal of young, all of which are potential colonizers. Of the ten or so environmental factors known to influence reproduction in house mice, seven probably are of routine importance in natural populations: diurnal modulation by daily light:dark cycles; caloric intake; nutrition; extreme temperature; agaonistic stimuli; socio-tactile cues; and priming pheronomes. The last two factors named operate directly on the secretion of luteinizing hormone or prolactin; the others act at many points in the reproductive system. Reproduction in the house mouse seems divorced from photoperiodically induced seasonality; indeed, this species breeds well even in constant darkness. Seasonal breeding may or may not then occur, depending upon dietary considerations, with or without a secondary interaction with variation in ambient temperature. There is no evidence for a dependence upon secondary plant compounds. Some of the effects of priming pheromones that have been observed previously in laboratory mice probably play no meaningful role in wild populations. The remaining pheromonal phenomena can be conceptualized as a single cueing system that has three components: (a) urinary cues of socially dominant males can accelerate ovulation in females, adult or prepubertal; (b) female urinary cues may elevate pheromonal potency in adult males, thereby forming a feedback loop by which the females elicit their own ovulation; and (c) the male's action on prepubertal females can be blocked by urinary cues emanating from other females. When all of the above is viewed in toto, the reproductive biology of the house mouse seems uniquely suited to support ecological opportunism. The relatively few environmental inhibitors of reproduction in this species should enhance the ability of dispersing young to colonize an exceptionally wide variety of habitats and climates...

Animals↗
PubMed2026

Reproduction on the Rocks: Life History of a Freshwater Macrobioeroding Bivalve.

Macrobioerosion, the excavation and removal of consolidated mineral substrates by macrofauna, is well established in marine systems, where macrobioeroders drive carbonate cycling, sediment production and habitat formation. In freshwater ecosystems, however, it has been documented in only a small number of invertebrate taxa and remains a poorly resolved ecological process. Among these, the teredinid shipworm Lithoredo abatanica represents a remarkable departure from the wood-boring ecology of its family, having evolved to excavate and ingest limestone in fresh water. Despite this remarkable ecological transition, its reproductive biology and life history remain unknown. Here, we investigate the reproductive mode and life history strategy of this species using population size structure, in&#xa0;situ observations of siphonal morphology, and sperm morphometrics. We show that L.&#x2009;abatanica reaches exceptional dimensions, with measured body lengths exceeding 100&#x2009;mm, one intact empty burrow exceeding 200&#x2009;mm and in-water observations indicating burrows possibly exceeding 500&#x2009;mm, establishing it as the largest known freshwater macrobioeroder. Its large size and dense aggregations indicate considerable capacity for local rock breakdown and habitat modification within the Abatan River system (Bohol, Philippines). Recently settled juveniles (<&#x2009;10&#x2009;mm) alongside reproductively mature individuals indicate ongoing recruitment. The morphology of the siphons and calcareous tube appears to preclude direct sperm transfer via pseudocopulation, while sperm morphometrics are consistent with external fertilisation. Together, these findings indicate that L.&#x2009;abatanica reproduces via broadcast spawning with external fertilisation and likely possesses a planktotrophic larval phase. This raises a fundamental question: how does a broadcast-spawning species with planktotrophic larvae maintain populations up to 15&#x2009;km upstream in a flowing freshwater river subject to persistent downstream advection? By resolving the life history of the largest known freshwater macrobioeroder, this study provides critical insight into the persistence, dispersal and ecological role of a globally unique riverine ecosystem engineer.

broadcast spawning↗
PubMed1975

Structure and function of immunoglobulins.

There are five major classes of immunoglobulins - IgG, M, A, D and E. Each is made of two heavy and two light chains or polymers of this basic subunit. The structure of each heavy and light chain consists of a variable region involved in antigen specificity and binding and a constant region which is involved in the class specific properties. The different classes of immunoglobulins differ in the biological properties. Of particular interest is the IgA fraction which provides antibodies in all the external secretions - including the reproductive organs. A few speculations are offered as to the possible role of IgA in reproductive biology.

Amino Acid Sequence↗
PubMed2025

Comparative genomics and transcriptomics of the Spiroplasma glossinidia strain sGff reveal insights into host interaction and trypanosome resistance in Glossina fuscipes fuscipes.

Tsetse (Glossina spp.) are vectors of African trypanosomes, the causative agents of Human and African Animal trypanosomiases, diseases that remain significant medical and socioeconomic challenges in sub-Saharan Africa. In addition to trypanosomes, tsetse harbor both obligate and facultative symbiotic bacteria that can influence vector competence and reproductive biology. One such facultative symbiont, Spiroplasma glossinidia, infects several tsetse species within the Palpalis subgroup. In Glossina fuscipes fuscipes (Gff), the Spiroplasma glossinidia strain sGff induces a trypanosome-refractory phenotype and negatively impacts reproductive fitness by reducing female fecundity. However, the mechanisms behind these Spiroplasma-derived phenotypes remain poorly understood. Here, we report successful in vitro cultivation of sGff and present complete genomes from three sources: in vitro cultured sGff and sGff isolated from both laboratory-maintained and wild-caught (Uganda) Gff flies. Comparative genomic analyses revealed a high degree of similarity in gene content and synteny among these sGff samples, confirming that they represent isolates of the same strain. Phylogenomic analyses placed sGff within the Spiroplasma poulsonii clade. The sGff genome is highly dynamic, containing numerous mobile genetic elements. Additionally, in silico annotations indicate that sGff relies on its host for both lipids and carbohydrates and produces several toxins, all of which could be implicated in the observed trypanosome refractory phenotype. Finally, comparative transcriptomic analysis of sGff from host hemolymph versus in vitro culture provided insights into potential factors relevant to host-symbiont interactions. Our findings provide a foundation for understanding the nutritional dialogue between sGff and its host and identify symbiotic products that may contribute to trypanosome resistance. Furthermore, the establishment of an in vitro culture system for sGff represents a significant resource for future functional studies with potential implications for vector control.

Glossina fuscipes fuscipes↗
PubMed1978

Use of the common marmoset, Callithrix jacchus, in reproductive research.

A self-sustaining colony of common marmosets, Callithrix jacchus, was established for reproductive research. Methods of management were developed to ensure optimal breeding conditions for marmosets in captivity. Studies of the reproductive biology and endocrinology of this species suggest that the common marmoset may be a suitable model for the human in certain aspects of the ovarian cycle, pregnancy, puberty and the hypothalamic and pituitary control of luteinizing hormone secretion. The rapid rate of reproduction of C. jacchus in captivity allows a relatively large colony to be maintained at moderate cost and also makes this species a most suitable laboratory primate for longer term studies of the safety and efficacy of new contraceptive methods.

Aging↗
PubMed2025

Tdrd15 is dispensable for male fertility and spermatogenesis in the golden hamster.

Tudor domain-containing proteins (TDRDs) constitute an evolutionarily conserved protein family and are critical for germline development and piRNA pathway regulation, with established roles in male fertility. While multiple TDRD family members have been functionally linked to spermatogenic impairment, the precise biological role of TDRD15 remains to be elucidated. We used CRISPR/Cas9-mediated gene editing to generate Tdrd15 knockout (KO) golden hamsters (Mesocricetus auratus), a model necessitated by the absence of a functional Tdrd15 ortholog in the mouse genome, to investigate its function in male reproduction. Phylogenetic analysis demonstrated that TDRD15 is strongly conserved among eutherian mammals, with testis-restricted expression patterns in hamsters. Despite the successful induction of frameshift mutations and significant transcriptional knockdown, Tdrd15 KO males maintained normal fertility parameters, including unaltered testicular architecture, spermatogenic progression (confirmed by periodic acidic-Schiff (PAS) staining and immunohistochemistry), and sperm quality metrics determined using a computer-assisted analysis. Quantitative polymerase chain reaction (qPCR) revealed compensatory overexpression of paralogous Tdrd genes in KO testes, implying functional redundancy within this protein family. This study provides the first experimental evidence that TDRD15 is dispensable for male fertility in golden hamsters under physiological conditions, thereby challenging the prevailing assumptions of its obligatory function in spermiogenesis. Altogether, these findings support a more targeted allocation of research efforts within the field of male reproductive biology.

Animals↗
PubMed1979

Female reproductive patterns in nonhibernating bats.

The major reproductive events in the oestrous cycles of nonhibernating mega- and microchiropteran species are reviewed. However, special attention is given to the reproductive biology of the temperate North American species, Tadarida brasiliensis mexicana (Molossidae), the Mexican free-tailed bat, which expresses dextral uterine and ovarian dominance. Only the larger right ovary is capable of producing an ovulatory follicle and the left has long been considered atrophic. In order to elucidate the normal oestrous cycle and define the structural and functional characteristics of the ovaries of this nonhibernating bat several analytical technique were utilized. These included light microscopic analysis, histochemical localization of delta 5-3 beta-hydroxysteroid dehydrogenase (HSD) activity, and radioimmunoassay of seasonal plasma progesterone levels. Interstitial tissue was found in both ovaries, but the left was almost entirely an interstitial organ. Histochemical analysis demonstrated that the gonads have seasonally varying amounts of delta 5-2 beta-HSD localized either in the thecal cells of the Graafian follicle or in the interstitium. The corpus luteum persisted throughout gestation, reaching maximum development just prior to parturition. Circulating progesterone levels correlated directly with luteal gland size and peaked at 106 ng/ml when the corpus luteum was largest.

Animals↗
PubMed2026

IL17 signaling promotes oocyte developmental competence acquisition during maturation.

BACKGROUND: Defects in the acquisition of oocyte developmental competence during the maturation process causes subfertility or infertility in animals and humans. Understanding the regulatory mechanisms of oocyte maturation is essential for reproductive biology and medicine. Follicular fluid (FF) is an important microenvironment governing oocyte maturation. METHODS: A tandem mass tags (TMT)-based comparative FF proteomic analysis was employed to identify FF proteins that are potentially crucial for oocyte maturation. A very large number of pig and mouse oocytes (approximately 20,000) and embryos (over 13,000, including somatic cell nuclear transfer, parthenogenetic activation, and in vitro fertilization embryos) were used to investigate the effects of identified FF proteins on in vitro oocyte maturation and subsequent in vitro and in vivo embryo development. RNA sequencing, quantitative PCR, enzyme-linked immunosorbent assays, and immunofluorescence were used to study the expression patterns and action mechanisms of identified FF proteins in oocytes. In addition, intra-oocyte levels of glutathione and reactive oxygen species were measured to assess redox homeostasis. RESULTS: Interleukin 17D (IL17D) was identified as an important FF protein and it is significantly upregulated in porcine FF during oocyte maturation. IL17D promotes oocyte maturation by enhancing bidirectional communication between oocytes and cumulus cells, via upregulating CX43 expression and transzonal projections, which helps to maintain oocyte redox homeostasis and nuclear-cytoplasmic synchrony. IL17D treatment of oocytes enhances subsequent in vitro and in vivo full-term embryo development by modulating lipid metabolism and histone modification reprogramming. IL17D exerts its function via activating IL17 signaling through binding to CD93. Two other IL17 family members, IL17A and IL17F, also enhance oocyte maturation quality. IL17D displays a conserved expression pattern and function in pig and mouse oocytes. CONCLUSIONS: This study reveals the critical roles of IL17D in regulating oocyte developmental competence acquisition during maturation by activating IL17 signaling. The findings provide valuable insights into the molecular mechanisms underlining oocyte developmental potential acquisition and may help to develop methods for efficient production of oocytes for assisted reproduction.

Animals↗
PubMed1977

Preimplantation development, fate of the zona pellucida, and observations on the glycogen-rich oviduct of the little bulldog bat, Noctilio albiventris.

The reproductive biology of Noctilio albiventris was investigated histologically in 112 females collected at the start of their synchronized breeding season during two different sampling years in the Cauca Valley of Colombia. Both ovaries were functional, but the animals were generally observed to be monovular. Embryonic development in the oviduct was found to proceed to blastocyst formation and loss of the zona pellucida. In 22 animals the discarded zona had been left behind in the oviduct upon passage of the embryo into the uterus and was still undissolved at the time of amniogenesis, the latest stage examined. The zonae which had passed into the uterus with the embryos often exhibited signs of dissolution. Most of the early blastocyts were morphologically distinctive, lacking a typical inner cell mass and being instead largely bilaminar. Degenerating ova from previous ovulations were found in the oviducts of two pregnant bats, suggesting that Noctilio may be another species in which the embryo stimulates its own escape from the oviduct. During tubal passage of the embryo the secretory cells of the oviductal ampulla and isthmus exhibited a transient engorgement with glycogen, particularly on the side ipsilateral to the new corpus luteum.

Animals↗
PubMed2026

PAT: An Image Analysis Tool for Automated Scoring of Pollen in Alexander-Stained Anthers.

Quantitative pollen viability analysis is a critical but labor-intensive step in plant reproductive biology. Existing deep-learning Segment Anything Models (SAM) fail to reliably segment viable pollen in Alexander-stained anthers. To address this, we fine-tuned an existing Cellpose-SAM model for pollen segmentation. We integrated it into PAT (Pollen Analysis Tool), a cross-platform desktop application. PAT features instance segmentation with interactive quality control, an in-app model retraining module, and publication-ready statistical outputs. We deployed PAT in an EMS suppressor screen of semi-sterile Arabidopsis smg7-6 mutants, enabling efficient candidate prioritization for whole-genome sequencing and mapping of the candidate mutation. This screen led to the identification of a point mutation in CAP-D2 (capd2-2), a Condensin I subunit, that rescues the smg7-6 meiotic phenotype. Notably, mutation in a Condensin II subunits (CAP-D3 and CAP-H2) does not confer rescue. Further characterization suggests the capd2-2 allele is hypomorphic, showing no defects in vegetative growth, chromocenter compaction, or transposable element silencing. Collectively, we demonstrate that accessible AI tools have the potential to bridge gaps in plant phenotyping and accelerate the pace of biological discovery.

Alexander staining↗
PubMed2026

Maternal DNA repair safeguards genome stability during the oocyte-to-embryo transition.

De novo mutations are a major source of genetic variation and disease risk, yet the developmental timing and mechanisms underlying their origin require further investigation. While germ cells have traditionally been considered the primary source of these mutations, increasing evidence suggests that a substantial fraction arise after fertilization. Here, we investigated the role of maternal DNA repair in shaping mutagenesis during this critical window by using a mouse model with oocyte-specific disruption of the homologous recombination factor RAD51 and a combination of cellular and molecular analyses. Loss of maternal RAD51 led to the accumulation of DNA double-strand breaks in oocytes without impairing their growth, meiotic maturation, or fertilization competence. In contrast, embryos derived from RAD51-deficient oocytes exhibited increased DNA damage and developmental delay during early cleavage stages. Whole-genome sequencing revealed a significant increase in de novo variants in offspring, the majority displaying intermediate allele frequencies consistent with post-zygotic mosaic mutations. These findings confirm that maternal DNA repair safeguards genome stability across the oocyte-to-embryo transition and identify early embryogenesis as a major source of de novo mutations, with implications for reproductive biology and the origins of genetic diseases.

DNA↗
PubMed1975

Infertility diagnosed by laparoscopy: review of 324 cases.

Reproductive biology has developed into a major subspecialty in gynecology. This study is a retrospective analysis of a private patient population in which the major presenting complaint was infertility. The 324 cases reviewed are divided into three groups: group1-congenital lesions (subdivided into anatomic defects and endocrine disorders); group 2-infectious disorders and genital neoplasias; and group 3-iatrogenic causes of anovulation. Direct visualization of the internal genitalia combined with a hysterogram gives positive proof of tubal patency and allows the surgeon to develop a plan of therapy. By visualizing the ovaries, he obtains the information necessary for the proper choice of ovulatory stimulating agents. Laparoscopy is not a new procedure but has been used increasingly in modern medicine. Better optic resolution and new operative instrumentation have been a great help to the fertility specialist. The laparoscope spans the gap between palpation and exploratory laparotomy.

Female↗
PubMed1976

Mixed cultures of sperm and leukocytes as a measure of histcompatibility in man.

Human peripheral blood leukocyte cultures containing varying numbers of washed fresh sperm were cultured for 4 days. [3H] Thymidine incorporation was used as a measure of lymphocyte transformation. Human sperm cells induce a 4- to 250-fold increase in [3H] thymidine incorporation in allogeneic leuocyte cultures, but no increase was demonstrated in autologous leukocyte cultures. The response was dose-dependent with maximum stimulation obtained at 2 x 10(6) sperm per milliliter of culture. Seminal plasma was inhibitory in a dose-dependent fashion and as little as 0.2 microliter per 200 microliters of culture was inhibitory. The data indicate that tissues other than leukocytes can express the portion of the major histocompatibility complex responsibile for allospecific lymphocyte transformation, and thus have application in transplantation and reproductive biology.

HLA Antigens↗