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[PMID]:28132863
[Au] Autor:Peel E; Belov K
[Ad] Endereço:Faculty of Veterinary Science, University of Sydney, Sydney, Australia. Electronic address: emma.peel@sydney.edu.au.
[Ti] Título:Immune-endocrine interactions in marsupials and monotremes.
[So] Source:Gen Comp Endocrinol;244:178-185, 2017 Apr 01.
[Is] ISSN:1095-6840
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Interactions between the immune and endocrine systems are not well studied in marsupials and monotremes. One exception to this is the phenomenon of semelparity, which is well covered in the literature as this is an unusual reproductive strategy amongst mammals and is only observed in some dasyurid and didelphid marsupials. Thymus involution provides a direct link between the endocrine and immune systems and warrants further study in marsupials and monotremes. The thymus is a primary immune tissue which is essential for overall immune function. Whilst the organ is large in juvenile animals, it begins to involute around puberty due to the suppressive effects of sex steroids. Thymus involution has a significant effect on the immune system, as it signals the onset of immune aging and decline in function. The output of naïve T lymphocytes by the thymus decreases, increasing susceptibility of aged individuals to infection and cancers. Understanding the links between the immune and endocrine system in marsupials and monotremes may shed light on diseases such as devil facial tumour disease (DFTD) which threatens the future of the Tasmanian devil. We hypothesise that changes in sex hormones around puberty may drive changes in the immune system, such as thymus involution, which may make devils more susceptible to DFTD as they age. In addition, the Schwann cell origin of DFTD may enable tumours to respond to sex hormones, as occurs in similar cancers in humans.
[Mh] Termos MeSH primário: Marsupiais/fisiologia
Monotremados/fisiologia
[Mh] Termos MeSH secundário: Animais
Seres Humanos
Maturidade Sexual/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170131
[St] Status:MEDLINE


  2 / 221 MEDLINE  
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[PMID]:27889918
[Au] Autor:Schultz JA; Zeller U; Luo ZX
[Ad] Endereço:Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, Illinois, 60637.
[Ti] Título:Inner ear labyrinth anatomy of monotremes and implications for mammalian inner ear evolution.
[So] Source:J Morphol;278(2):236-263, 2017 Feb.
[Is] ISSN:1097-4687
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The monophyletic clade Monotremata branches early from the rest of the mammalian crown group in the Jurassic and members of this clade retain many ancestral mammalian traits. Thus, accurate and detailed anatomical descriptions of this group can offer unique insight into the early evolutionary history of Mammalia. In this study, we examine the inner ear anatomy of two extant monotremes, Ornithorhynchus anatinus and Tachyglossus aculeatus, with the primary goals of elucidating the ancestral mammalian ear morphology and resolving inconsistencies found within previous descriptive literature. We use histological serial sections and high-resolution microcomputed tomography (µCT) for correlating soft tissue features of the vestibule and cochlea to the osseous labyrinth endocast. We found that in both monotremes the scala tympani coils to a lesser degree than scala vestibuli and scala media, although all three scalae show an apical coil inside the osseous cochlear tube. The helicotrema (conduit between scala tympani and scala vestibuli) is in subapical position, and the cochlear and lagenar ganglia and their associated nerve fibers are not enclosed by bone. In comparison, in extant therian mammals (i.e., marsupials and placentals) the helicotrema is located at the apex of the osseous cochlear canal, the three scalae coil to the same degree and the cochlear ganglion is enclosed by the primary bony lamina. Whether the lagenar ganglion is lost in therian mammals or integrated into the cochlear ganglion is still debated. The presence of a sensory lagenar macula at the apex of the membranous cochlear duct, innervated by a separate lagenar nerve and ganglion is a plesiomorphic condition of amniotes that monotremes share. A separate osseous lagenar canaliculus for the lagenar nerve, and the coiling of the distended lagenar sac at the end of the cochlear duct are autapomorphies of monotremes. Based on our findings we hypothesize that the ancestral inner ear of stem mammaliaforms is characterized by a straight or slightly curved osseous cochlear canal, a lagenar macula, lagenar nerve fibers separated from a larger bundle of cochlear nerve fibers, the presence of an organ of Corti and an intra-otic cochlear ganglion suspended by membranous connective tissue. Among the major Mesozoic clades of crown mammals, cladotherians and gondwanatherians most likely acquired a fully functioning organ of Corti but lost the sensory lagenar macula, like extant therians. However, Mesozoic spalacotherioids, multituberculates and eutriconodonts likely retained the mammaliaform condition. J. Morphol. 278:236-263, 2017. © 2016 Wiley Periodicals,Inc.
[Mh] Termos MeSH primário: Orelha Interna/anatomia & histologia
Monotremados/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Evolução Biológica
Microtomografia por Raio-X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170815
[Lr] Data última revisão:
170815
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161128
[St] Status:MEDLINE
[do] DOI:10.1002/jmor.20632


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[PMID]:26431612
[Au] Autor:Deakin JE
[Ad] Endereço:Institute for Applied Ecology, University of Canberra, Canberra, ACT 2601, Australia. Electronic address: Janine.Deakin@canberra.edu.au.
[Ti] Título:Implications of monotreme and marsupial chromosome evolution on sex determination and differentiation.
[So] Source:Gen Comp Endocrinol;244:130-138, 2017 Apr 01.
[Is] ISSN:1095-6840
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Studies of chromosomes from monotremes and marsupials endemic to Australasia have provided important insight into the evolution of their genomes as well as uncovering fundamental differences in their sex determination/differentiation pathways. Great advances have been made this century into solving the mystery of the complicated sex chromosome system in monotremes. Monotremes possess multiple different X and Y chromosomes and a candidate sex determining gene has been identified. Even greater advancements have been made for marsupials, with reconstruction of the ancestral karyotype enabling the evolutionary history of marsupial chromosomes to be determined. Furthermore, the study of sex chromosomes in intersex marsupials has afforded insight into differences in the sexual differentiation pathway between marsupials and eutherians, together with experiments showing the insensitivity of the mammary glands, pouch and scrotum to exogenous hormones, led to the hypothesis that there is a gene (or genes) on the X chromosome responsible for the development of either pouch or scrotum. This review highlights the major advancements made towards understanding chromosome evolution and how this has impacted on our understanding of sex determination and differentiation in these interesting mammals.
[Mh] Termos MeSH primário: Evolução Biológica
Marsupiais/genética
Monotremados/genética
Monotremados/fisiologia
Cromossomos Sexuais/genética
[Mh] Termos MeSH secundário: Animais
Feminino
Masculino
Marsupiais/fisiologia
Análise para Determinação do Sexo
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151004
[St] Status:MEDLINE


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[PMID]:27395568
[Au] Autor:Spratt DM; Beveridge I
[Ad] Endereço:Australian National Wildlife Collection, CSIRO National Research Facilities, GPO Box 1700, Canberra. A.C.T. 2601, Australia; Email: dave.spratt@csiro.au.
[Ti] Título:Helminth parasites of Australasian monotremes and marsupials.
[So] Source:Zootaxa;4123(1):1-198, 2016 Jun 15.
[Is] ISSN:1175-5334
[Cp] País de publicação:New Zealand
[La] Idioma:eng
[Ab] Resumo:This work includes all published records, to April 2015, of the helminths occurring in Australasian monotremes and marsupials, with due regard for synonymy and an attempt to include life history studies, pathological observations and epidemiology. It also contains all unpublished records known to us and referrable, by accession numbers, to curated collections in Australia and overseas. Information is presented by host family, genus, species, sub-species or chromosome race and includes the names of all host species from which no parasites have been recorded. Most records pertain to free-living and wild animals; where they do not, they have been annotated appropriately. Unpublished information known to the authors has been included in annotations to entries, where appropriate. Parasites are arranged as follows: Trematoda, Cestoda, Nematoda, Acanthocephala, and their systematic position is indicated by abbreviations placed before the name. The authority for each parasite record is given after the author's name, as a number in parentheses, and this refers to the numbered (1-664) list of references.        A parasite-host list is presented alphabetically, irrespective of taxonomic affiliation together with the host species in which they are known to occur. Hosts are arranged initially by family and alphabetically within each family.
[Mh] Termos MeSH primário: Helmintíase Animal/parasitologia
Helmintos/isolamento & purificação
Marsupiais/parasitologia
Monotremados/parasitologia
[Mh] Termos MeSH secundário: Animais
Austrália
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170302
[Lr] Data última revisão:
170302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160711
[St] Status:MEDLINE
[do] DOI:10.11646/zootaxa.4123.1.1


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[PMID]:27173752
[Au] Autor:Mitchelle A; Watson C
[Ad] Endereço:Faculty of Medicine, Notre Dame University, Perth, WA, Australia.
[Ti] Título:The organization of spinal motor neurons in a monotreme is consistent with a six-region schema of the mammalian spinal cord.
[So] Source:J Anat;229(3):394-405, 2016 09.
[Is] ISSN:1469-7580
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The motor neurons in the spinal cord of an echidna (Tachyglossus aculeatus) have been mapped in Nissl-stained sections from spinal cord segments defined by spinal nerve anatomy. A medial motor column of motor neurons is found at all spinal cord levels, and a hypaxial column is found at most levels. The organization of the motor neuron clusters in the lateral motor column of the brachial (C5 to T3) and crural (L2 to S3) limb enlargements is very similar to the pattern previously revealed by retrograde tracing in placental mammals, and the motor neuron clusters have been tentatively identified according to the muscle groups they are likely to supply. The region separating the two limb enlargements (T4 to L1) contains preganglionic motor neurons that appear to represent the spinal sympathetic outflow. Immediately caudal to the crural limb enlargement is a short column of preganglionic motor neurons (S3 to S4), which it is believed represents the pelvic parasympathetic outflow. The rostral and caudal ends of the spinal cord contain neither a lateral motor column nor a preganglionic column. Branchial motor neurons (which are believed to supply the sternomastoid and trapezius muscles) are present at the lateral margin of the ventral horn in rostral cervical segments (C2-C4). These same segments contain the phrenic nucleus, which belongs to the hypaxial column. The presence or absence of the main spinal motor neuron columns in the different regions echidna spinal cord (and also in that of other amniote vertebrates) provides a basis for dividing the spinal cord into six main regions - prebrachial, brachial, postbrachial, crural, postcrural and caudal. The considerable biological and functional significance of this subdivision pattern is supported by recent studies on spinal cord hox gene expression in chicks and mice. On the other hand, the familiar 'segments' of the spinal cord are defined only by the anatomy of adjacent vertebrae, and are not demarcated by intrinsic gene expression. The recognition of segments defined by vertebrae (somites) is obviously of great value in defining topography, but the emphasis on such segments obscures the underlying evolutionary reality of a spinal cord comprised of six genetically defined regions. The six-region system can be usefully applied to the spinal cord of any amniote (and probably most anurans), independent of the number of vertebral segments in each part of the spinal column.
[Mh] Termos MeSH primário: Monotremados/anatomia & histologia
Neurônios Motores/citologia
Medula Espinal/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Feminino
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170821
[Lr] Data última revisão:
170821
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160514
[St] Status:MEDLINE
[do] DOI:10.1111/joa.12492


  6 / 221 MEDLINE  
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[PMID]:26763693
[Au] Autor:Ramírez-Chaves HE; Wroe SW; Selwood L; Hinds LA; Leigh C; Koyabu D; Kardjilov N; Weisbecker V
[Ad] Endereço:School of Biological Sciences, University of Queensland, Goddard Building 8, St Lucia 4072, Australia h.ramirezchaves@uq.edu.au.
[Ti] Título:Mammalian development does not recapitulate suspected key transformations in the evolutionary detachment of the mammalian middle ear.
[So] Source:Proc Biol Sci;283(1822), 2016 Jan 13.
[Is] ISSN:1471-2954
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The ectotympanic, malleus and incus of the developing mammalian middle ear (ME) are initially attached to the dentary via Meckel's cartilage, betraying their origins from the primary jaw joint of land vertebrates. This recapitulation has prompted mostly unquantified suggestions that several suspected--but similarly unquantified--key evolutionary transformations leading to the mammalian ME are recapitulated in development, through negative allometry and posterior/medial displacement of ME bones relative to the jaw joint. Here we show, using µCT reconstructions, that neither allometric nor topological change is quantifiable in the pre-detachment ME development of six marsupials and two monotremes. Also, differential ME positioning in the two monotreme species is not recapitulated. This challenges the developmental prerequisites of widely cited evolutionary scenarios of definitive mammalian middle ear (DMME) evolution, highlighting the requirement for further fossil evidence to test these hypotheses. Possible association between rear molar eruption, full ME ossification and ME detachment in marsupials suggests functional divergence between dentary and ME as a trigger for developmental, and possibly also evolutionary, ME detachment. The stable positioning of the dentary and ME supports suggestions that a 'partial mammalian middle ear' as found in many mammaliaforms--probably with a cartilaginous Meckel's cartilage--represents the only developmentally plausible evolutionary DMME precursor.
[Mh] Termos MeSH primário: Evolução Biológica
Orelha Média/anatomia & histologia
Mamíferos/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Dentição
Orelha Média/crescimento & desenvolvimento
Mamíferos/crescimento & desenvolvimento
Marsupiais/anatomia & histologia
Marsupiais/crescimento & desenvolvimento
Monotremados/anatomia & histologia
Monotremados/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1610
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160115
[St] Status:MEDLINE


  7 / 221 MEDLINE  
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[PMID]:26644330
[Au] Autor:Ashwell KW; Shulruf B
[Ad] Endereço:Department of Anatomy, School of Medical Sciences, The University of New South Wales, Sydney, NSW, Australia.
[Ti] Título:Quantitative comparison of cerebral artery development in metatherians and monotremes with non-human eutherians.
[So] Source:J Anat;228(3):384-95, 2016 Mar.
[Is] ISSN:1469-7580
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A quantitative comparison of the internal diameters of cerebral feeder arteries (internal carotid and vertebral) and the aorta in developing non-human eutherians, metatherians and monotremes has been made, with the aim of determining if there are differences in cerebral arterial flow between the three infraclasses of mammals such as might reflect differences in metabolism of the developing brain. There were no significant differences between eutherians and metatherians in the internal radius of the aorta or the thickness of the aortic wall, but aortic internal radius was significantly smaller in developing monotremes than therians at the < 10 mm body length range. Aortic thickness in the developing monotremes also rose at a slower rate relative to body length than in metatherians or eutherians. The sums of the internal calibres of the internal carotid and vertebral arteries were significantly lower in metatherians as a group and monotremes compared with non-human eutherians at body lengths up to 20 mm and in metatherians at > 20 mm body length. The internal calibre of the internal carotids relative to the sum of all cerebral feeder arteries was also significantly lower in monotremes at < 10 mm body length compared with eutherians. It was noted that dasyurids differed from other metatherians in several measures of cerebral arterial calibre and aortic internal calibre. The findings suggest that: (i) both aortic outflow and cerebral arterial inflow may be lower in developing monotremes than in therians, particularly at small body size (< 20 mm); (ii) cerebral inflow may be lower in some developing metatherians than non-human eutherians; and (iii) dasyurids have unusual features of cerebral arteries possibly related to the extreme immaturity and small size at which they are born. The findings have implications for nutritional sourcing of the developing brain in the three infraclasses of mammals.
[Mh] Termos MeSH primário: Artérias Cerebrais/crescimento & desenvolvimento
Marsupiais/crescimento & desenvolvimento
Monotremados/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Animais
Circulação Cerebrovascular/fisiologia
Mamíferos/crescimento & desenvolvimento
Especificidade da Espécie
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Em] Mês de entrada:1610
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151209
[St] Status:MEDLINE
[do] DOI:10.1111/joa.12422


  8 / 221 MEDLINE  
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[PMID]:26523413
[Au] Autor:Vaz PK; Hartley CA; Browning GF; Devlin JM
[Ad] Endereço:Asia-Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia. Electronic address: pvaz@unimelb.edu.au.
[Ti] Título:Marsupial and monotreme serum immunoglobulin binding by proteins A, G and L and anti-kangaroo antibody.
[So] Source:J Immunol Methods;427:94-9, 2015 Dec.
[Is] ISSN:1872-7905
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Serological studies are often conducted to examine exposure to infectious agents in wildlife populations. However, specific immunological reagents for wildlife species are seldom available and can limit the study of infectious diseases in these animals. This study examined the ability of four commercially available immunoglobulin-binding reagents to bind serum immunoglobulins from 17 species within the Marsupialia and Monotremata. Serum samples were assessed for binding, using immunoblots and ELISAs (Enzyme-linked immunosorbent assays), to three microbially-derived proteins - staphylococcal protein A, streptococcal protein G and peptostreptococcal protein L. Additionally, an anti-kangaroo antibody was included for comparison. The inter- and intra-familial binding patterns of the reagents to serum immunoglobulins varied and evolutionary distance between animal species was not an accurate predictor of the ability of reagents to bind immunoglobulins. Results from this study can be used to inform the selection of appropriate immunological reagents in future serological studies in these clades.
[Mh] Termos MeSH primário: Imunoglobulinas/imunologia
Macropodidae/imunologia
Monotremados/imunologia
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/imunologia
Ensaio de Imunoadsorção Enzimática
Immunoblotting
Marsupiais/imunologia
Proteína Estafilocócica A/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Ig L-binding protein, Peptostreptococcus); 0 (IgG Fc-binding protein, Streptococcus); 0 (Immunoglobulins); 0 (Staphylococcal Protein A)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:151215
[Lr] Data última revisão:
151215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:151103
[St] Status:MEDLINE


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[PMID]:26235095
[Au] Autor:Ashwell KW
[Ad] Endereço:a Department of Anatomy , School of Medical Sciences, The University of New South Wales , New South Wales, 2052 , Australia.
[Ti] Título:Timing of mammalian peripheral trigeminal system development relative to body size: A comparison of metatherians with rodents and monotremes.
[So] Source:Somatosens Mot Res;32(3):187-99, 2015.
[Is] ISSN:1369-1651
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Specializations of the trigeminal sensory system are present in all three infraclasses of mammals (metatheria, eutheria, prototheria or monotremata). The trigeminal sensory system has been suggested as a critically important modality for sampling the path to the pouch and detecting the nipple or milk patch, but the degree to which that system may be required to function at birth varies significantly. Archived sections of the snout and brainstem of embryonic and postnatal mammals were used to test the relationship between structural maturity of the two ends of the trigeminal nerve pathway and the body size of mammalian young in metatherians, rodents and monotremes. A system for staging different levels of structural maturity of the vibrissae and trigeminal sensory was applied to embryos, pouch young and hatchlings and correlated with body length. Dasyurids are born at the most immature state with respect to vibrissal and trigeminal sensory nucleus development of any available metatherian, but these components of the trigeminal system are also developmentally advanced relative to body size when dasyurids are compared to other metatherians. Vibrissal and trigeminal sensory nucleus development is at a similar stage of development at birth and for a given body size in non-dasyurid metatherians; and trigeminal sensory nucleus development in monotremes is at a similar stage at birth to metatherians. Rodents reach a far more advanced stage of vibrissal and trigeminal sensory nucleus development at birth than do metatherians, and in the case of the mouse have a more developmentally advanced trigeminal system than all available metatherians at any given body length. Precocious development of the trigeminal sensory pathway relative to body size is evident in dasyurids, as might be expected given the small birth size of those metatherians. Nevertheless, the trigeminal sensory system in metatherians in general is not precocious relative to body size when these species are considered alongside the pace of trigeminal somatosensory development in rodents.
[Mh] Termos MeSH primário: Tamanho Corporal
Marsupiais/fisiologia
Monotremados/fisiologia
Roedores/fisiologia
Nervo Trigêmeo/fisiologia
Núcleos do Trigêmeo/fisiologia
[Mh] Termos MeSH secundário: Vias Aferentes/fisiologia
Fatores Etários
Animais
Animais Recém-Nascidos
Evolução Biológica
Embrião de Mamíferos
Especificidade da Espécie
Nervo Trigêmeo/anatomia & histologia
Núcleos do Trigêmeo/anatomia & histologia
Vibrissas/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1606
[Cu] Atualização por classe:150924
[Lr] Data última revisão:
150924
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150804
[St] Status:MEDLINE


  10 / 221 MEDLINE  
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[PMID]:26213206
[Au] Autor:Peter A; Khandekar S; Deakin JE; Stick R
[Ad] Endereço:Department of Cell Biology, FB2, University of Bremen, P.O. Box 33 04 40, 28334 Bremen, Germany.
[Ti] Título:A peculiar lamin in a peculiar mammal: Expression of lamin LIII in platypus (Ornithorhynchus anatinus).
[So] Source:Eur J Cell Biol;94(11):522-30, 2015 Nov.
[Is] ISSN:1618-1298
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Platypus (Ornithorhynchus anatinus) holds a unique phylogenetic position at the base of the mammalian lineage due to an amalgamation of mammalian and sauropsid-like features. Here we describe the set of four lamin genes for platypus. Lamins are major components of the nuclear lamina, which constitutes a main component of the nucleoskeleton and is involved in a wide range of nuclear functions. Vertebrate evolution was accompanied by an increase in the number of lamin genes from a single gene in their closest relatives, the tunicates and cephalochordates, to four genes in the vertebrate lineage. Of the four genes the LIII gene is characterized by the presence of two alternatively spliced CaaX-encoding exons. In amphibians and fish LIII is the major lamin protein in oocytes and early embryos. The LIII gene is conserved throughout the vertebrate lineage, with the notable exception of marsupials and placental mammals, which have lost the LIII gene. Here we show that platypus has retained an LIII gene, albeit with a significantly altered structure and with a radically different expression pattern. The platypus LIII gene contains only a single CaaX-encoding exon and the head domain together with coil 1a and part of coil1b of the platypus LIII protein is replaced by a novel short non-helical N-terminus. It is expressed exclusively in the testis. These features resemble those of male germ cell-specific lamins in placental mammals, in particular those of lamin C2. Our data suggest (i) that the specific functions of LIII, which it fulfills in all other vertebrates, is no longer required in mammals and (ii) once it had been freed from these functions has undergone structural alterations and has adopted a new functionality in monotremes.
[Mh] Termos MeSH primário: Laminas/genética
Monotremados/genética
[Mh] Termos MeSH secundário: Processamento Alternativo
Sequência de Aminoácidos
Animais
Sequência de Bases
Laminas/química
Laminas/metabolismo
Masculino
Dados de Sequência Molecular
Monotremados/metabolismo
Especificidade de Órgãos
Filogenia
Estrutura Terciária de Proteína
Testículo/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lamins)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:151102
[Lr] Data última revisão:
151102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150728
[St] Status:MEDLINE



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