Identification of a germ-cell-specific transcriptional repressor in the promoter of Tctex-1

The Tctex-1 gene family maps to the t complex of the mouse and consists of four copies on chromosome 17 in both wild-type and t-haplotypes. Tctex-1 mRNA is eightfold overexpressed in male and female germ cells in t-haplotype compound heterozygotes (tx/ty). In order to determine the cause of this aberrant expression and the role of this gene family in spermatogenesis and oogenesis it was subjected to extensive molecular analysis. We find that Tctex-1 protein is present in sperm tails and oocytes and that it is present at equal levels in wild-type and t-haplotype testis. Surprisingly, the excess message in t-haplotypes is not translated. Sequence analysis of the gene family reveals that one copy in t-haplotypes has a mutated start codon. This same copy is deleted for a protein-binding motif in its promoter. This motif, GIM (Germ cell Inhibitory Motif) has strong homology to the Xenopus AP-2-binding site but does not appear to be a binding site for mammalian AP-2. A factor(s) present in testis and ovary, but absent in other mouse tissues binds specifically to this site. Transfection assays using Tctex-1 promoter constructs suggest that GIM functions as a transcriptional repressor. The possible role of Tctex-1 in t complex transmission ratio distortion and sterility is discussed.

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Genetic evidence for two t complex tail interaction (tct) loci in t haplotypes.

Genetics ◽

10.1093/genetics/122.4.895 ◽

1989 ◽

Vol 122 (4) ◽

pp. 895-903

Author(s):

J H Nadeau ◽

D Varnum ◽

D Burkart

Keyword(s):

Genetic Analysis ◽

Tail Length ◽

Genetic Interactions ◽

Chromosome 17 ◽

Wild Type ◽

T Complex ◽

Inverted Duplication ◽

Haplotype A ◽

Recombination Breakpoints ◽

T Haplotype

Abstract The t complex on chromosome 17 of the house mouse is an exceptional model for studying the genetic control of transmission ratio, gametogenesis, and embryogenesis. Partial haplotypes derived through rare recombination between a t haplotype and its wild-type homolog have been essential in the genetic analysis of these various properties of the t complex. A new partial t haplotype, which was derived from the complete tw71 haplotype and which is called tw71Jr1, was shown to have unexpected effects on tail length and unique recombination breakpoints. This haplotype, either when homozygous or when heterozygous with the progenitor tw71 haplotype, produced short-tailed rather than normal-tailed mice on certain genetic backgrounds. Genetic analysis of this exceptional haplotype showed that the recombination breakpoints were different from those leading to any other partial t haplotype. Based on this haplotype, a model is proposed that accounts for genetic interactions between the brachyury locus (T), the t complex tail interaction (tct) locus, and their wild-type homolog(s) that determine tail length. An important part of this model is the hypothesis that the tct locus, which enhances the tail-shortening effect of T mutations, is in fact at least two, genetically separable genes with different genetic activities. Genetic analysis of parental and recombinant haplotypes also suggests that intrachromosomal recombination involving an inverted duplicated segment can account for the variable orientation of loci within an inverted duplication on wild-type homologs of the t haplotype.

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Genetic exchange across a paracentric inversion of the mouse t complex.

Genetics ◽

10.1093/genetics/128.4.799 ◽

1991 ◽

Vol 128 (4) ◽

pp. 799-812 ◽

Cited By ~ 1

Author(s):

M F Hammer ◽

S Bliss ◽

L M Silver

Keyword(s):

Inbred Strains ◽

Genetic Exchange ◽

Transmission Ratio Distortion ◽

Chromosome 17 ◽

Wild Type ◽

T Complex ◽

Haplotype Allele ◽

Hybrid Allele ◽

Paracentric Inversions ◽

T Haplotype

Abstract Mouse t haplotypes are distinguished from wild-type forms of chromosome 17 by four nonoverlapping paracentric inversions which span a genetic distance of 20 cM. These inversion polymorphisms are responsible for a 100-200-fold suppression of recombination which maintains the integrity of complete t haplotypes and has led to their divergence from the wild-type chromosomes of four species of house mice within which t haplotypes reside. As evidence for the long period of recombinational isolation, alleles that distinguish all t haplotypes from all wild-type chromosomes have been established at a number of loci spread across the 20-cM variant region. However, a more complex picture emerges upon analysis of other t-associated loci. In particular, "mosaic haplotypes" have been identified that carry a mixture of wild-type and t-specific alleles. To investigate the genetic basis for mosaic chromosomes, we conducted a comprehensive analysis of eight t complex loci within 76 animals representing 10 taxa in the genus Mus, and including 23 previously characterized t haplotypes. Higher resolution restriction mapping and sequence analysis was also performed for alleles at the Hba-ps4 locus. The results indicate that a short tract of DNA was transferred relatively recently across an inversion from a t haplotype allele of Hba-ps4 to the corresponding locus on a wild-type homolog leading to the creation of a new hybrid allele. Several classes of wild-type Hba-ps4 alleles, including the most common form in inbred strains, appear to be derived from this hybrid allele. The accumulated data suggest that a common form of genetic exchange across one of the four t-associated inversions is gene conversion at isolated loci that do not play a role in the transmission ratio distortion phenotype required for t haplotype propagation. The implications of the results pose questions concerning the evolutionary stability of gene complexes within large paracentric inversions and suggest that recombinational isolation may be best established for loci residing within a short distance from inversion breakpoints.

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Regulation of the cognitive aging process by the transcriptional repressor RP58

10.1101/2021.09.18.460879 ◽

2021 ◽

Author(s):

Tomoko Tanaka ◽

Shinobu Hirai ◽

Hiroyuki Manabe ◽

Kentaro Endo ◽

Hiroko Shimbo ◽

...

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Knockout Mice ◽

Cognitive Aging ◽

Critical Role ◽

Harmful Effect ◽

Transcriptional Repressor ◽

Repair Pathway ◽

Wild Type

Aging involves a decline in physiology which is a natural event in all living organisms. An accumulation of DNA damage contributes to the progression of aging. DNA is continually damaged by exogenous sources and endogenous sources. If the DNA repair pathway operates normally, DNA damage is not life threatening. However, impairments of the DNA repair pathway may result in an accumulation of DNA damage, which has a harmful effect on health and causes an onset of pathology. RP58, a zinc-finger transcriptional repressor, plays a critical role in cerebral cortex formation. Recently, it has been reported that the expression level of RP58 decreases in the aged human cortex. Furthermore, the role of RP58 in DNA damage is inferred by the involvement of DNMT3, which acts as a co-repressor for RP58, in DNA damage. Therefore, RP58 may play a crucial role in the DNA damage associated with aging. In the present study, we investigated the role of RP58 in aging. We used RP58 hetero-knockout and wild-type mice in adolescence, adulthood, or old age. We performed immunohistochemistry to determine whether microglia and DNA damage markers responded to the decline in RP58 levels. Furthermore, we performed an object location test to measure cognitive function, which decline with age. We found that the wild-type mice showed an increase in single-stranded DNA and gamma-H2AX foci. These results indicate an increase in DNA damage or dysfunction of DNA repair mechanisms in the hippocampus as age-related changes. Furthermore, we found that, with advancing age, both the wild-type and hetero-knockout mice showed an impairment of spatial memory for the object and increase in reactive microglia in the hippocampus. However, the RP58 hetero-knockout mice showed these symptoms earlier than the wild-type mice did. These results suggest that a decline in RP58 level may lead to the progression of aging.

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Genetic and molecular analysis of the proximal region of the mouse t-complex using new molecular probes and partial t-haplotypes.

Genetics ◽

10.1093/genetics/126.4.1103 ◽

1990 ◽

Vol 126 (4) ◽

pp. 1103-1114 ◽

Cited By ~ 1

Author(s):

C A Howard ◽

G R Gummere ◽

M F Lyon ◽

D Bennett ◽

K Artzt

Keyword(s):

Wild Mouse ◽

Molecular Probes ◽

Proximal Region ◽

Chromosome 17 ◽

Lethal Gene ◽

Strong Linkage Disequilibrium ◽

Wild Type ◽

T Complex ◽

Naturally Occurring ◽

Normal Transmission

Abstract The t-complex is located on the proximal third of chromosome 17 in the house mouse. Naturally occurring variant forms of the t-complex, known as complete t-haplotypes, are found in wild mouse populations. The t-haplotypes contain at least four nonoverlapping inversions that suppress recombination with the wild-type chromosome, and lock into strong linkage disequilibrium loci affecting normal transmission of the chromosome, male gametogenesis and embryonic development. Partial t-haplotypes derived through rare recombination between t-haplotypes and wild-type homologs have been critical in the analysis of these properties. Utilizing two new DNA probes. Au3 and Au9, and several previously described probes, we have analyzed the genetic structure of several partial t-haplotypes that have arisen in our laboratory, as well as several wild-type chromosomes deleted for loci in this region. With this approach we have been able to further our understanding of the structural and dynamic characteristics of the proximal region of the t-complex. Specifically, we have localized the D17Tul locus as most proximal known in t-haplotypes, achieved a better structural analysis of the partial t-haplotype t6, and defined the structure and lethal gene content of partial t-haplotypes derived from the lethal tw73 haplotype.

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The Two ADF-H Domains of Twinfilin Play Functionally Distinct Roles in Interactions with Actin Monomers

Molecular Biology of the Cell ◽

10.1091/mbc.e02-03-0157 ◽

2002 ◽

Vol 13 (11) ◽

pp. 3811-3821 ◽

Cited By ~ 55

Author(s):

Pauli J. Ojala ◽

Ville O. Paavilainen ◽

Maria K. Vartiainen ◽

Roman Tuma ◽

Alan G. Weeds ◽

...

Keyword(s):

Binding Site ◽

Binding Activity ◽

Size Exclusion ◽

Actin Dynamics ◽

Actin Binding ◽

Actin Monomer ◽

Wild Type ◽

Native Page ◽

Exclusion Chromatography

Twinfilin is a ubiquitous and abundant actin monomer–binding protein that is composed of two ADF-H domains. To elucidate the role of twinfilin in actin dynamics, we examined the interactions of mouse twinfilin and its isolated ADF-H domains with G-actin. Wild-type twinfilin binds ADP-G-actin with higher affinity (K D = 0.05 μM) than ATP-G-actin (K D = 0.47 μM) under physiological ionic conditions and forms a relatively stable (k off = 1.8 s−1) complex with ADP-G-actin. Data from native PAGE and size exclusion chromatography coupled with light scattering suggest that twinfilin competes with ADF/cofilin for the high-affinity binding site on actin monomers, although at higher concentrations, twinfilin, cofilin, and actin may also form a ternary complex. By systematic deletion analysis, we show that the actin-binding activity is located entirely in the two ADF-H domains of twinfilin. Individually, these domains compete for the same binding site on actin, but the C-terminal ADF-H domain, which has >10-fold higher affinity for ADP-G-actin, is almost entirely responsible for the ability of twinfilin to increase the amount of monomeric actin in cosedimentation assays. Isolated ADF-H domains associate with ADP-G-actin with rapid second-order kinetics, whereas the association of wild-type twinfilin with G-actin exhibits kinetics consistent with a two-step binding process. These data suggest that the association with an actin monomer induces a first-order conformational change within the twinfilin molecule. On the basis of these results, we propose a kinetic model for the role of twinfilin in actin dynamics and its possible function in cells.

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BAX regulates follicular endowment in mice

Reproduction ◽

10.1530/rep-06-0270 ◽

2007 ◽

Vol 133 (5) ◽

pp. 865-876 ◽

Cited By ~ 60

Author(s):

Chuck R Greenfeld ◽

Melissa E Pepling ◽

Janice K Babus ◽

Priscilla A Furth ◽

Jodi A Flaws

Keyword(s):

Cell Viability ◽

Germ Cell ◽

Proliferative Activity ◽

Primordial Germ Cell ◽

Initial Endowment ◽

Regulatory Activity ◽

Wild Type ◽

X Protein ◽

Primordial Follicles

It is believed that the endowment of primordial follicles in mammalian ovaries is finite. Once follicles are depleted, infertility ensues. Thus, the size of the initial endowment has consequences for fertility and reproductive longevity. Follicular endowment is comprised of various processes that culminate with the incorporation of meiosis-arrested oocytes into primordial follicles. Apoptosis is prominent during follicular endowment, and apoptosis regulatory genes are involved in its regulation. Conflicting data exist with regard to the role of the proapoptotic Bcl-2 associated X protein (BAX) in follicular endowment. Therefore, we investigated the role of BAX during follicular endowment in embryonic and neonatal ovaries. We found that BAX is involved in regulating follicular endowment in mice. Deletion ofBaxyields increased oocyte numbers in embryonic ovaries and increased follicle numbers in neonatal ovaries when compared with wild-type ovaries. Increased follicular endowment inBax−/−ovaries is not due to enhanced germ cell viability. Further, it is not due to an increased primordial germ cell (PGC) allotment, a delay in the onset of meiosis, or altered proliferative activity of oogonia. Instead, our data suggest that the regulatory activity of BAX in follicular endowment likely occurs during PGC migration, prior to PGC colonization of the gonad.

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Distorter genes of the mouse t-complex impair male fertility when heterozygous

Genetics Research ◽

10.1017/s0016672300026732 ◽

1987 ◽

Vol 49 (1) ◽

pp. 57-60 ◽

Cited By ~ 18

Author(s):

Mary F. Lyon

Keyword(s):

Male Fertility ◽

Genetic Background ◽

Inbred Strains ◽

Transmission Ratio Distortion ◽

Chromosome 17 ◽

Male Mice ◽

Wild Type ◽

T Complex ◽

Ratio Distortion ◽

Harmful Effects

SummaryMale mice heterozygous for two distorter genes, Tcd-1 and Tcd-2, of the mouse t-complex but homozygous wild type for the responder, were generated by crossing animals carrying the partial t-haplotypes th51 and th18 to inbred strains. The fertility of these males was then compared with that of their brothers carrying normal chromosome 17s. On three of the inbred backgrounds used, C3H/HeH, C57BL/6J and TFH/H, the th51th18 + / + + + males were significantly less fertile than their normal sibs. With the fourth inbred strain used, SM/JH, both types of male were nonnally fertile. This confirmed earlier preliminary findings that when both homologues of chromosome 17 carry wild-type alleles of the responder, heterozygosity for the distorter genes is sufficient to impair fertility, but the effect varies with genetic background. These results are consistent with the concept that both the transmission ratio distortion and the male sterility caused by the t-complex are due to harmful effects of the distorter genes on wild-type alleles of the responder.

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Role of Cyclin D3 in the Biology of Herpes Simplex Virus 1 ICP0

Journal of Virology ◽

10.1128/jvi.75.4.1888-1898.2001 ◽

2001 ◽

Vol 75 (4) ◽

pp. 1888-1898 ◽

Cited By ~ 38

Author(s):

Charles Van Sant ◽

Pascal Lopez ◽

Sunil J. Advani ◽

Bernard Roizman

Keyword(s):

Cyclin D1 ◽

Binding Site ◽

Mutant Virus ◽

Cyclin D3 ◽

Wild Type Virus ◽

Cell Protein ◽

Cyclin D ◽

Wild Type ◽

Human Embryonic Lung

ABSTRACT Earlier reports from this laboratory have shown that the promiscuous transactivator infected-cell protein 0 (ICP0) binds and stabilizes cyclin D3, that the binding site maps to aspartic acid 199 (D199), and that replacement of D199 with alanine abolishes binding and reduces the capacity of the mutant virus to replicate in quiescent cells or to cause mortality in mice infected by a peripheral site. The objective of this report was to investigate the role of cyclin D3 in the biology of ICP0. We report the following results. (i) Wild-type ICP0 activates cyclin D-dependent kinase 4 (cdk4) and stabilizes cyclin D1 although ICP0 does not interact with this cyclin. (ii) The D199A mutant virus (R7914) does not activate cdk4 or stabilize cyclin D1, and neither the wild-type nor the mutant virus activates cdk2. (iii) Early in infection of human embryonic lung (HEL) fibroblasts both wild-type and D199A mutant ICP0s colocalize with PML, and in these cells the ND10 nuclear structures are dispersed. Whereas wild-type ICP0 is transported to the cytoplasm between 3 and 9 h. after infection, ICPO containing the D199A substitution remains quantitatively in the nucleus. (iv) To examine the interaction of ICP0 with cyclin D3, we used a previously described mutant carrying a wild-type ICP0 but expressing cyclin D3 (R7801) and in addition constructed a virus (R7916) that was identical except that it carried the D199A-substituted ICP0. Early in infection with R7801, ICP0 colocalized with cyclin D3 in structures similar to those containing PML. At 3 h after infection, ICP0 was translocated to the cytoplasm whereas cyclin D3 remained in the nucleus. The translocation of ICP0 to the cytoplasm was accelerated in cells expressing cyclin D3 compared with that of ICP0 expressed by wild-type virus. In contrast, ICP0 carrying the D199A substitution remained in the nucleus and did not colocalize with cyclin D3. These studies suggest the following conclusions. (i) ICP0 brings to the vicinity of ND10 cyclin D3 and, in consequence, an activated cdk4. The metabolic events occurring at or near that structure and involving cyclin D3 cause the translocation of ICP0 to the cytoplasm. (ii) In the absence of the cyclin D3 binding site in ICP0, cyclin D3 is not brought to ND10, cyclin D is not stabilized, and the function responsible for the translocation of ICP0 is not expressed, and in quiescent HEL fibroblasts the yields of virus are reduced.

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t-Specific DNA polymorphisms among wild mice from Israel and Spain.

Genetics ◽

10.1093/genetics/119.1.157 ◽

1988 ◽

Vol 119 (1) ◽

pp. 157-160

Author(s):

F Figueroa ◽

E Neufeld ◽

U Ritte ◽

J Klein

Keyword(s):

Laboratory Mouse ◽

The Other ◽

Dna Polymorphisms ◽

Chromosome 17 ◽

Mouse Strains ◽

Laboratory Mice ◽

Wild Type ◽

Wild Mice ◽

T Complex ◽

Length Polymorphisms

Abstract Lehrach and his coworkers have isolated a series of DNA probes that specifically hybridize with different regions of mouse chromosome 17 within the t complex. The probes display restriction fragment length polymorphisms, RFLPs, which are specific for the t haplotypes in all laboratory mouse strains tested thus far. Some of these probes have been used to test wild mice populations for these t-associated DNA forms. It is demonstrated that populations from Germany, Switzerland, Italy, Greece, Yugoslavia, Australia, Costa Rica, and Venezuela contain chromosomes in which all the tested DNA loci display the t-specific polymorphisms. The frequency of mice carrying these chromosomes is as high as 31%. Wild mice from Israel and Spain, on the other hand, carry chromosomes displaying t-specific DNA forms only at one or two of the probed loci, while the other loci carry the wild-type (+) forms. These chromosomes thus resemble the partial t haplotypes known from the study of laboratory mice. One possible interpretation of these findings is that these DNA polymorphisms contributed to the assembly of the complete t haplotypes and that these haplotypes may have originated in the Middle East.

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Leukocyte integrin Mac-1 regulates thrombosis via interaction with platelet GPIbα

Nature Communications ◽

10.1038/ncomms15559 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 45

Author(s):

Yunmei Wang ◽

Huiyun Gao ◽

Can Shi ◽

Paul W. Erhardt ◽

Alexander Pavlovsky ◽

...

Keyword(s):

Transcription Factor ◽

Carotid Artery ◽

Binding Site ◽

Small Molecule ◽

Therapeutic Potential ◽

Bleeding Risk ◽

Disease Models ◽

Wild Type ◽

Microvascular Injury

Abstract Inflammation and thrombosis occur together in many diseases. The leukocyte integrin Mac-1 (also known as integrin αMβ2, or CD11b/CD18) is crucial for leukocyte recruitment to the endothelium, and Mac-1 engagement of platelet GPIbα is required for injury responses in diverse disease models. However, the role of Mac-1 in thrombosis is undefined. Here we report that mice with Mac-1 deficiency (Mac-1 −/− ) or mutation of the Mac-1-binding site for GPIbα have delayed thrombosis after carotid artery and cremaster microvascular injury without affecting parameters of haemostasis. Adoptive wild-type leukocyte transfer rescues the thrombosis defect in Mac-1 −/− mice, and Mac-1-dependent regulation of the transcription factor Foxp1 contributes to thrombosis as evidenced by delayed thrombosis in mice with monocyte-/macrophage-specific overexpression of Foxp1. Antibody and small-molecule targeting of Mac-1:GPIbα inhibits thrombosis. Our data identify a new pathway of thrombosis involving leukocyte Mac-1 and platelet GPIbα, and suggest that targeting this interaction has anti-thrombotic therapeutic potential with reduced bleeding risk.

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