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1.
Notf Rett Med ; : 1-10, 2023 Jun 15.
Article in German | MEDLINE | ID: mdl-37363068

ABSTRACT

Background: In the event of emergency response to large-scale incidents, such as a mass casualty incident (MCI) or a mass casualty incident-infectious disease (MCI-ID), regular training is essential in order to have experienced emergency personnel available in the event of an incident. Due to the pandemic drills often had to be cancelled or were only possible with small groups of people. It was often not possible to simulate a large-scale emergency with actors, so that the trainees could not be offered realistic scenarios of a mass casualty or disease incident. As part of two research projects, a digital platform for conducting training was used to avoid the risk of infection between participants during the exercises, so that on-site personnel deployment could be reduced to a minimum. The goal of this work was to evaluate end-user acceptance of the digital solution approaches. Methods: Within the framework of the project "Adaptive Resilience Management in Ports" (ARMIHN), a digital exercise platform was applied and evaluated with the help of participant surveys according to the focal points "implementation", "alternative possibilities", "learning effect" and "usability". The participants used the digital platform to exchange information and to communicate. For this purpose, various collaboration tools were embedded in the platform, which enabled simultaneous exchange of information in real time. Constant video communication with in-house and external authorities/teams was also established. Results: The potential of the digital platform as an alternative to on-site exercises was confirmed by the participating end users in the ARMIHN project with 90% agreement. The increase in subjective skills and knowledge gained during a MCI-ID was also predominantly rated approvingly (up to 70%). Participants who rated the implementation of the online format as well performed were significantly more likely to state that subjectively their ability to handle a MCI-ID had improved (p = 0.016). In contrast, virtual staff teamwork in real crisis situations was viewed critically by about half of respondents. Conclusion: Overall, the evaluation results point to the high end-user acceptance of the developed concept. Even though the aim is to evaluate the system over a longer period with a larger number of participants, the studies already conducted confirm the positive experiences in the respective projects.

2.
J Occup Med Toxicol ; 16(1): 36, 2021 Aug 31.
Article in English | MEDLINE | ID: mdl-34465347

ABSTRACT

BACKGROUND: The project "ARMIHN" (Adaptive Resiliency Management in Port) focuses on strengthening the capability to act in a mass casualty incident (MCI) due to an outbreak of infectious diseases (MCI-ID). In addition to the current threat from the COVID-19 pandemic and associated outbreaks on cruise ships, previous MCI-ID were especially caused by pathogens such as Influenza virus or Norovirus. The first step was, to get an overview of processes and resources using the example of the Port of Hamburg, and to show the associated interaction of involved parties. This will serve as a basis for developing an operational strategy and offers the opportunity to optimize current work processes. METHODS: A selective literature research using specified key words was performed and existing MCI concepts were received from local authorities. Identified structures and processes were analyzed in a multiple step process and also brought together through discussions in workshops with involved organizations and other experts. Additionally, the distances between the nearest rescue stations and selected hospitals from the Port of Hamburg were analyzed. RESULTS: The current available concepts are proven, but an adaptation to an MCI-ID shows opportunities for a further cross-organizational development. The organizational structure of an MCI-ID in the Port of Hamburg was described, including a large number of involved organizations (n = 18). There are 17 involved fire and rescue stations and the port can be reached from these locations within 6 to 35 min. Based on their specialist expertise, 14 of the 31 listed clinics were selected. CONCLUSION: The purpose of the study was to provide an analysis of the current situation and show how involved parties would cope an MCI. A description of processes and resources at the Port of Hamburg will be used when designing a management plan for responding to an MCI-ID.

3.
J Occup Med Toxicol ; 16(1): 41, 2021 Sep 14.
Article in English | MEDLINE | ID: mdl-34521438

ABSTRACT

BACKGROUND: Food choices on board merchant ships are limited and seafarers repeatedly described as being at high risk of developing overweight compared to the general population. Up to date, research has not distinguished whether seafarers gain weight on board or at home and whether eating habits differ in both settings. METHODS: As part of the e-healthy ship project, cross-sectional data were collected in two different measurements. In the first investigation on board of three merchant ships of German shipping companies, differences in eating behaviour at home compared to on board ships were assessed for 18 Burmese, 26 Filipino and 20 European seafarers. In a second study, BMI, weight development and location of body weight change of 543 Filipino and 277 European seafarers were examined using an online questionnaire on 68 ships. RESULTS: According to the board examinations, foods and beverages consumed on merchant ships varied widely from seafarers' diets in their home country. Burmese, Filipino and European seafarers equally reported to consume more fruit (z = 4.95, p < .001, r = .62) and vegetables (z = 6.21, p < .001, r = .79), but less coke (z = -5.00, p < .001, r = .76) when at home. Furthermore, culturally different changes were found across all other foods and beverages. The online questionnaire revealed that 45.8% of seafarers were overweight (55.4% Europeans vs. 40.8% Filipinos, p < .001) and 9.8% obese. Moreover, a higher percentage of Europeans compared to Filipinos reported weight gain over the course of their professional career (50.2% vs. 40.7%, p = .007). A sub-analysis of seafarers with weight gain found that more Europeans than Filipinos gained weight at home (43.9% vs. 23.1%, p < .001). CONCLUSIONS: Both, home and working on board merchant ships, represent very different living environments which may affect seafarers' lifestyle and eating habits in various ways and thus could favour or inhibit weight gain. From our results, it appears that the body weight and eating habits of Asian seafarers in particular are adversely affected by the working and living conditions on board. Further prospective studies are required to prove this hypothesis.

4.
Article in German | MEDLINE | ID: mdl-34456517

ABSTRACT

BACKGROUND: A pandemic is a particular medical challenge for seafarers traveling without a physician on board. At the same time the global fight against the coronavirus disease 2019 (COVID-19) pandemic has to rely on resilient merchant shipping in order to maintain the flow of goods. For infection prevention and management on board, those responsible need a portfolio of protective measures that can be used on ships. RESEARCH QUESTIONS: The overview examines the question of which technical, organizational and personal protective measures can be used on a merchant ship in order to prevent or cope with COVID-19 outbreaks on board. MATERIAL AND METHODS: Guidelines, information and occupational health and safety standards from the maritime setting, but also from many other work areas, were examined in order to facilitate a variable use by those responsible (e.g. according to ship size, equipment, weather, operating status, work requirements, contact with external persons, medical problems). RESULTS: A handout was compiled that contains specific technical, organizational and personal protective measures for crews, explaining their use in a maritime context. Possible safety barriers, options to combine them and an appropriate timing are explained in a target group-oriented manner. CONCLUSION: A great variety of protective measures derived from occupational medical literature and the experience of the port medical service in Hamburg can also be implemented on the high seas. In pandemic times, merchant ships should be equipped with foresight (e.g. with rapid diagnostic tests) and those responsible should be authorized to use effective infection control measures adapted to the situation on board. Seafarers should receive priority vaccination offers regardless of their national origin.

5.
Article in English | MEDLINE | ID: mdl-34068311

ABSTRACT

The confined environment of a ship promotes the transmission of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) due to close contact among the population on board. The study aims to provide an overview of outbreaks of SARS-CoV-2 on board of cruise, navy or cargo ships, to identify relevant outbreak management techniques, related problems and to derive recommendations for prevention. Four databases were searched. The study selection included reports about seroprevalences or clinically/laboratory confirmed infections of SARS-CoV-2 on board ships between the first of January, 2020 and the end of July, 2020. A total of 37 studies were included of whom 33 reported outbreaks of SARS-CoV-2 on cruise ships (27 studies referred to the Diamond Princess). Two studies considered outbreaks on the Grand Princess, three studies informed about Nile River cruises and one study about the MS Westerdam (mention of multiple outbreaks possible in one study). Additionally, three studies reported outbreaks of SARS-CoV-2 on navy vessels and one study referred to a cargo ship. Problems in handling outbreaks resulted from a high number of asymptomatic infections, transportation issues, challenges in communication or limited access to health care. Responsible operators need to implement infection control measures which should be described in outbreak management plans for ships to prevent transmission risks, including, e.g., education, testing strategies, communication lines, social distancing and hygiene regulations.


Subject(s)
COVID-19 , Ships , Disease Outbreaks , Government Agencies , Humans , SARS-CoV-2
6.
Article in German | MEDLINE | ID: mdl-33730194

ABSTRACT

COVID-19 has been challenging our society since January 2020. Due to global travel, the new coronavirus has rapidly spread worldwide. This article aims to provide an overview of the challenges in implementing measures in the air and maritime transport sector from the perspective of the German Public Health Service (Öffentlicher Gesundheitsdienst, ÖGD). Significant events and measures for air and maritime transport between January and August 2020 were selected. Lessons learned are discussed.During the COVID-19 pandemic, the ÖGD has been operating in a field of tension between the dynamics of scientific knowledge, political decision-making, social acceptance and consent.There are specific challenges at points of entry such as airports and seaports. These include staff shortages and the need to implement measures with a high organisational effort at very short notice such as health authority passenger checks carried out on aircraft, the establishment of test centres at points of entry and control of compliance with quarantine measures. Aggravating the situation, passenger lists, which are necessary for effective contact tracing, are often not available or incomplete. There is also a lack of digital tools for contact tracing but also, for example, the exchange of personal data within the ÖGD. Further difficulties in outbreak management arise from the cramped conditions on board ships and from the potential psychological stress on crew members and passengers, which have not yet been sufficiently considered.In view of all these challenges, it is paramount to strengthen the German Public Health Service in general and at points of entry and to intensify the exchange between the national, federal state and local levels.


Subject(s)
COVID-19 , Pandemics , Germany/epidemiology , Health Services , Humans , Pandemics/prevention & control , Public Health , Quarantine , SARS-CoV-2
8.
Proc Natl Acad Sci U S A ; 109(18): 7115-20, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22517751

ABSTRACT

Pod corn is a classic morphological mutant of maize in which the mature kernels of the cob are covered by glumes, in contrast to generally grown maize varieties in which kernels are naked. Pod corn, known since pre-Columbian times, is the result of a dominant gain-of-function mutation at the Tunicate (Tu) locus. Some classic articles of 20th century maize genetics reported that the mutant Tu locus is complex, but molecular details remained elusive. Here, we show that pod corn is caused by a cis-regulatory mutation and duplication of the ZMM19 MADS-box gene. Although the WT locus contains a single-copy gene that is expressed in vegetative organs only, mutation and duplication of ZMM19 in Tu lead to ectopic expression of the gene in the inflorescences, thus conferring vegetative traits to reproductive organs.


Subject(s)
Genes, Plant , Mutation , Zea mays/genetics , Alleles , Base Sequence , Chromosome Mapping , DNA, Plant/genetics , Evolution, Molecular , Gene Duplication , Gene Expression Regulation, Plant , Genes, Regulator , Genetic Complementation Test , MADS Domain Proteins/genetics , Molecular Biology , Molecular Sequence Data , Phenotype , Plant Leaves/growth & development , Plant Proteins/genetics , Polymorphism, Restriction Fragment Length , Sequence Homology, Nucleic Acid , Zea mays/growth & development
9.
Mol Biol Evol ; 27(5): 1201-11, 2010 May.
Article in English | MEDLINE | ID: mdl-20080864

ABSTRACT

Land plants (embryophytes) are characterized by an alternation of two generations, the haploid gametophyte and the diploid sporophyte. The development of the small and simple male gametophyte of the flowering plant Arabidopsis (Arabidopsis thaliana) critically depends on the action of five MIKC* group MCM1-AGAMOUS-DEFICIENS-SRF-box (MADS-box) proteins. In this study, these MIKC* MADS-box genes were isolated from land plants with relatively large and complex gametophyte bodies, namely the bryophytes. We found that although the gene family expanded in the mosses Sphagnum subsecundum, Physcomitrella patens, and Funaria hygrometrica, only a single homologue, Marchantia polymorpha MADS-box gene 1 (MpMADS1), has been retained in the liverwort M. polymorpha. Liverworts are the earliest diverging land plants, and so a comparison of MpMADS1 with its angiosperm homologues addresses the molecular evolution of an embryophyte-specific transcription factor over the widest phylogenetic distance. MpMADS1 was found to form a homodimeric DNA-binding complex, which is in contrast to the Arabidopsis proteins that are functional only as heterodimeric complexes. The M. polymorpha homodimer, nevertheless, recognizes the same DNA sequences as its angiosperm counterparts and can functionally replace endogenous MIKC* complexes to a significant extent when heterologously expressed in Arabidopsis pollen. The 11 MIKC* homologues from the moss F. hygrometrica are highly and almost exclusively expressed in the gametophytic generation. Taken together, these findings suggest that MIKC* MADS-box proteins have largely preserved molecular roles in the gametophytic generation of land plants.


Subject(s)
Bryopsida/genetics , Conserved Sequence , Germ Cells, Plant/growth & development , MADS Domain Proteins/genetics , Plant Proteins/genetics , Arabidopsis/cytology , Arabidopsis/genetics , Base Sequence , DNA, Plant/genetics , DNA, Plant/metabolism , Gene Expression Regulation, Plant , Genes, Plant/genetics , Genetic Complementation Test , MADS Domain Proteins/metabolism , Molecular Sequence Data , Mutation/genetics , Phylogeny , Plant Proteins/metabolism , Protein Binding , Protein Multimerization , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/metabolism
10.
Genome Biol ; 8(11): R249, 2007.
Article in English | MEDLINE | ID: mdl-18034896

ABSTRACT

BACKGROUND: Differentiation processes are responsible for the diversity and functional specialization of the cell types that compose an organism. The outcome of these processes can be studied at molecular, physiologic, and biochemical levels by comparing different cell types, but the complexity and dynamics of the regulatory processes that specify the differentiation are largely unexplored. RESULTS: Here we identified the pollen-specific MIKC* class of MADS-domain transcription factors as major regulators of transcriptome dynamics during male reproductive cell development in Arabidopsis thaliana. Pollen transcript profiling of mutants deficient in different MIKC* protein complexes revealed that they control a transcriptional switch that directs pollen maturation and that is essential for pollen competitive ability. We resolved the functional redundancy among the MIKC* proteins and uncovered part of the underlying network by identifying the non-MIKC* MADS-box genes AGL18 and AGL29 as downstream regulators of a subset of the MIKC* MADS-controlled genes. CONCLUSION: Our results provide a first, unique, and compelling insight into the complexity of a transcription factor network that directs cellular differentiation during pollen maturation, a process that is essential for male reproductive fitness in flowering plants.


Subject(s)
Pollen/genetics , RNA, Messenger/genetics , Transcription Factors/physiology , Arabidopsis/genetics , Base Sequence , DNA Primers , Mutation , Nucleic Acid Hybridization , Oligonucleotide Array Sequence Analysis
11.
Gene ; 401(1-2): 28-37, 2007 Oct 15.
Article in English | MEDLINE | ID: mdl-17689888

ABSTRACT

To come to a better understanding of the evolution and function of the SBP-box transcription factor family in plants, we identified, isolated and characterized 13 of its members from the moss Physcomitrella patens. For the majority of the moss SBP-box genes, clear orthologous relationships with family members of flowering plants could be established by phylogenetic analysis based on the conserved DNA-binding SBP-domain, as well as additional synapomorphic molecular characters. The P. patens SBP-box genes cluster in four separable groups. One of these consists exclusively of moss genes; the three others are shared with family members of Arabidopsis and rice. Besides the family defining DNA-binding SBP-domain, other features can be found conserved between moss and other plant SBP-domain proteins. An AHA-like motif conserved from the unicellular alga Chlamydomonas reinhardtii to flowering plants, was found able to promote transcription in a heterologous yeast system. The conservation of a functional microRNA response element in the mRNA of three of the moss SBP-box genes supports the idea of an ancient origin of microRNA dependent regulation of SBP-box gene family members. As our current knowledge concerning the roles of SBP-box genes in plant development is scarce and the model system P. patens allows targeted mutation, the material we isolated and characterized will be helpful to generate the mutant phenotypes necessary to further elucidate these roles.


Subject(s)
Bryopsida/genetics , Cycadopsida/genetics , Genes, Plant , Magnoliopsida/genetics , Plant Proteins/genetics , Amino Acid Motifs , Amino Acid Sequence , Arabidopsis/genetics , Bryopsida/classification , Cluster Analysis , DNA, Complementary , DNA, Plant/genetics , DNA, Plant/isolation & purification , Exons , Genetic Variation , Introns , MicroRNAs/genetics , Molecular Sequence Data , Multigene Family/genetics , Oryza/genetics , Phylogeny , Protein Structure, Tertiary , RNA, Messenger/genetics , Response Elements/genetics , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Transcription, Genetic
12.
Gene ; 400(1-2): 25-34, 2007 Oct 01.
Article in English | MEDLINE | ID: mdl-17614216

ABSTRACT

To date, the function of MADS-domain transcription factors in non-seed plants remains largely elusive, although a number of genes have been isolated and characterized from a variety of species. In our study we analyzed PPM2, a classical MIKC-type MADS-box gene from the moss Physcomitrella patens, taking advantage of the unique technical properties Physcomitrella offers in terms of efficient homologous recombination. We determined mRNA and protein distribution and performed targeted disruption of the genomic locus for functional analysis of PPM2. Despite weak ubiquitous expression, PPM2 protein is mostly found in male and female gametangia and basal parts of developing sporophytes. Therefore, PPM2 seems to function in both the haploid and the diploid phase of the moss life cycle. This situation reflects an evolutionary transition state of gene recruitment from an ancestral gametophytic generation into a derived sporophytic generation which became dominating in tracheophytes. However, a knock-out of the PPM2 gene did not cause visible phenotypical changes in the respective structures. The implications of our findings for the understanding of the evolutionary history of MADS-box transcription factors in plants are discussed.


Subject(s)
Bryophyta/genetics , Genes, Plant , MADS Domain Proteins/genetics , 5' Untranslated Regions , Alternative Splicing , Biological Evolution , Evolution, Molecular , Germ Cells/metabolism , MADS Domain Proteins/metabolism , RNA, Messenger/metabolism , Transgenes
13.
Plant Physiol ; 143(1): 447-60, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17071640

ABSTRACT

The genome of Arabidopsis (Arabidopsis thaliana) encodes over 100 MADS-domain transcription factors, categorized into five phylogenetic subgroups. Most research efforts have focused on just one of these subgroups (MIKC(c)), whereas the other four remain largely unexplored. Here, we report on five members of the so-called Mdelta or Arabidopsis MIKC* (AtMIKC*) subgroup, which are predominantly expressed during the late stages of pollen development. Very few MADS-box genes function in mature pollen, and from this perspective, the AtMIKC* genes are therefore highly exceptional. We found that the AtMIKC* proteins are able to form multiple heterodimeric complexes in planta, and that these protein complexes exhibit a for the MADS-family unusual and high DNA binding specificity in vitro. Compared to their occurrence in promoters genome wide, AtMIKC* binding sites are strongly overrepresented in the proximal region of late pollen-specific promoters. By combining our experimental data with in silico genomics and pollen transcriptomics approaches, we identified a considerable number of putative direct target genes of the AtMIKC* transcription factor complexes in pollen, many of which have known or proposed functions in pollen tube growth. The expression of several of these predicted targets is altered in mutant pollen in which all AtMIKC* complexes are affected, and in vitro germination of this mutant pollen is severely impaired. Our data therefore suggest that the AtMIKC* protein complexes play an essential role in transcriptional regulation during late pollen development.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/genetics , MADS Domain Proteins/metabolism , Promoter Regions, Genetic , Arabidopsis/metabolism , Arabidopsis Proteins/classification , Arabidopsis Proteins/genetics , Binding Sites , Cloning, Molecular , DNA, Complementary/chemistry , Gene Expression Regulation, Plant , Genomics , Germination/genetics , Germination/physiology , MADS Domain Proteins/classification , MADS Domain Proteins/genetics , Molecular Sequence Data , Pollen/genetics , Pollen/growth & development , Pollen/metabolism , RNA, Messenger/metabolism , Sequence Analysis, DNA
14.
Proc Natl Acad Sci U S A ; 102(7): 2436-41, 2005 Feb 15.
Article in English | MEDLINE | ID: mdl-15699346

ABSTRACT

The MADS-box genes of land plants are extensively diverged to form a superfamily and are important in various aspects of development including the specification of floral organs as homeotic selector genes. The closest relatives of land plants are the freshwater green algae charophyceans. To study the origin and evolution of land plant MADS-box genes, we characterized these genes in three charophycean green algae: the stonewort Chara globularis, the coleochaete Coleochaete scutata, and the desmid Closterium peracerosum-strigosum-littorale complex. Phylogenetic analyses suggested that MADS-box genes diverged extensively in the land plant lineage after the separation of charophyceans from land plants. The stonewort C. globularis mRNA was specifically detected in the oogonium and antheridium together with the egg and spermatozoid during their differentiation. The expression of the C. peracerosum-strigosum-littorale-complex gene increased when vegetative cells began to differentiate into gametangial cells and decreased after fertilization. These expression patterns suggest that the precursors of land plant MADS-box genes originally functioned in haploid reproductive cell differentiation and that the haploid MADS-box genes were recruited into a diploid generation during the evolution of land plants.


Subject(s)
Characeae/genetics , Chlorophyta/genetics , DNA, Algal/genetics , Algal Proteins/genetics , Amino Acid Sequence , Base Sequence , Chara/genetics , Evolution, Molecular , Exons , Introns , MADS Domain Proteins/genetics , Molecular Sequence Data , Phylogeny , Sequence Homology, Amino Acid
15.
Neuroradiology ; 46(7): 565-70, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15258709

ABSTRACT

The internal jugular veins are considered to be the main pathways of cerebral blood drainage. However, angiographic and anatomical studies show a wide anatomical variability and varying degrees of jugular and non-jugular venous drainage. The study systematically analyses the types and prevalence of human cerebral venous outflow patterns by ultrasound and MRI. Fifty healthy volunteers (21 females; 29 males; mean age 27+/-7 years) were studied by color-coded duplex sonography. Venous blood volume flow was measured in both internal jugular and vertebral veins in the supine position. Furthermore, the global arterial cerebral blood volume flow was calculated as the sum of volume flows in both internal carotid and vertebral arteries. Three types of venous drainage patterns were defined: a total jugular volume flow of more than 2/3 (type 1), between 1/3 and 2/3 (type 2) and less than 1/3 (type 3) of the global arterial blood flow. 2D TOF MR-venography was performed exemplarily in one subject with type-1 and in two subjects with type-3 drainage. Type-1 drainage was present in 36 subjects (72%), type 2 in 11 subjects (22%) and type 3 in 3 subjects (6%). In the majority of subjects in our study population, the internal jugular veins were indeed the main drainage vessels in the supine body position. However, a predominantly non-jugular drainage pattern was found in approximately 6% of subjects.


Subject(s)
Cerebral Veins/diagnostic imaging , Cerebrovascular Circulation , Jugular Veins/diagnostic imaging , Adult , Cerebral Veins/anatomy & histology , Female , Humans , Jugular Veins/anatomy & histology , Male , Posture , Ultrasonography, Doppler, Transcranial
16.
FEBS Lett ; 567(1): 147-51, 2004 Jun 01.
Article in English | MEDLINE | ID: mdl-15165908

ABSTRACT

Floral morphological novelties, like homeotic changes of whorl 1 organs, can easily arise by modifying existing regulatory networks. Ectopic expression of B-function MADS-box genes in whorl 1 leads to a replacement of sepals by petals, as is found in the Liliaceae. In cases where leaf-like sepals or even inflated calyces develop, which ultimately envelop the mature fruit as in Physalis, ectopic expression of a vegetative MADS-box gene seems to be responsible. Current knowledge concerning the origin of such morphological novelties is reviewed.


Subject(s)
Flowers/physiology , MADS Domain Proteins/physiology , Transcription Factors/physiology , Biological Evolution , Gene Expression Regulation, Plant , Genes, Plant , Genetic Variation , MADS Domain Proteins/genetics , Phenotype , Plant Proteins/physiology , Protein Structure, Tertiary
17.
Mol Biol Evol ; 19(6): 801-14, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12032236

ABSTRACT

Characterization of seven MADS-box genes, termed PPM1-PPM4 and PpMADS1-PpMADS3, from the moss model species Physcomitrella patens is reported. Phylogeny reconstructions and comparison of exon-intron structures revealed that the genes described here represent two different classes of homologous, yet distinct, MIKC-type MADS-box genes, termed MIKC(c)-type genes-"(c)" stands for "classic"-(PPM1, PPM2, PpMADS1) and MIKC(*)-type genes (PPM3, PPM4, PpMADS2, PpMADS3). The two gene classes deviate from each other in a characteristic way, especially in a sequence stretch termed intervening region. MIKC(c)-type genes are abundantly present in all land plants which have been investigated in this respect, and give rise to well-known gene types such as floral meristem and organ identity genes. In contrast, LAMB1 from the clubmoss Lycopodium annotinum was identified as the only other MIKC(*)-type gene published so far. Our findings strongly suggest that the most recent common ancestor of mosses and vascular plants contained at least one MIKC(c)-type and one MIKC(*)-type gene. Our studies thus reveal an ancient duplication of an MIKC-type gene that occurred before the separation of the lineages that led to extant mosses and vascular plants more than about 450 MYA. The identification of bona fide K-domains in both MIKC(*)-type and MIKC(c)-type proteins suggests that the K-domain is more ancient than is suggested by a recent alternative hypothesis. MIKC(*)-type genes may have escaped identification in ferns and seed plants so far. It seems more likely, however, that they represent a class of genes which has been lost in the lineage which led to extant ferns and seed plants. The high number of P. patens MADS-box genes and the presence of a K-box in the coding region and of some potential binding sites for MADS-domain proteins and other transcription factors in the putative promoter regions of these genes suggest that MADS-box genes in mosses are involved in complex gene regulatory networks similar to those in flowering plants.


Subject(s)
Bryopsida/genetics , MADS Domain Proteins/genetics , Amino Acid Sequence , MADS Domain Proteins/classification , MADS Domain Proteins/metabolism , Molecular Sequence Data , Phylogeny , Sequence Alignment , Sequence Analysis, DNA
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