scholarly journals VH gene expression is restricted in anti-IgG antibodies from MRL autoimmune mice.

1986 ◽  
Vol 164 (4) ◽  
pp. 1284-1300 ◽  
Author(s):  
S E Arant ◽  
J A Griffin ◽  
W J Koopman
Keyword(s):  
Gene Expression ◽  
Gene Family ◽  
Molecular Mechanisms ◽  
Gene Families ◽  
Igg Antibodies ◽  
Intact Mouse ◽  
Cytoplasmic Rna ◽  
Vh Gene ◽  
Rna Blots ◽  
Mrl Mouse

Antibodies directed against IgG and DNA are found in the sera of autoimmune MRL/Mp lpr/lpr mice. Little is known of the molecular mechanisms underlying expression of such autoantibodies. We have investigated the binding diversity and pattern of VH gene expression in a panel of murine anti-IgG antibodies. We constructed eight hybridoma clones secreting IgM antibodies that bound to mouse IgG by using spleen cells from MRL/Mp lpr/lpr mice varying in age from 4 to 15 wk; one clone was derived from a 32-wk-old MRL +/+ mouse. The monoclonal IgM products exhibited varying binding specificities for intact mouse IgG, fragments of mouse IgG [Fc, Fab, (Fab')2], and heterologous IgG. Two of these antibodies crossreacted with B and/or Z DNA. Probes from seven of eight identified mouse VH gene families (7183, S107, Q52, J558, J606, 36-60, and 3609) were hybridized under high-stringency conditions with cytoplasmic RNA blots from each clone. Six clones hybridized only with the probe from the five-member 36-60 family. The remaining three clones crosshybridized with the 36-60 probe and the probe from the 60 member J558 family, perhaps reflecting somatic mutation from the original germline VH gene resulting in recognition by a probe from another family, in addition to the probe from the original germline family. Our results indicate that spontaneous MRL lpr/lpr anti-IgG antibodies are encoded predominantly by the 36-60 VH gene family and imply a nonrandom selection of this VH gene family in the production of these antibodies.

scholarly journals Murine V kappa gene expression does not follow the VH paradigm.

1989 ◽  
Vol 169 (5) ◽  
pp. 1859-1864 ◽  
Author(s):  
A Kaushik ◽  
D H Schulze ◽  
C Bona ◽  
G Kelsoe
Keyword(s):  
Gene Expression ◽  
Gene Family ◽  
B Lymphocytes ◽  
Gene Rearrangement ◽  
Gene Families ◽  
Genomic Complexity ◽  
Positional Bias ◽  
Vh Gene

V kappa gene family expression among LPS-reactive murine B lymphocytes, unlike that of VH gene families, is not proportional to genomic complexity, i.e., nonstoichiometric. Furthermore, no positional bias for the overexpression of J-proximal V kappa genes (V kappa 21) is observed among neonatal B lymphocytes. Yet, the V kappa 1 and V kappa 9 families located in the center of V kappa locus are preferentially used by neonatal B splenocytes. Thus, the mechanisms of V kappa gene rearrangement and expression appear to differ significantly from those controlling the VH locus.

scholarly journals Inter-species functional compatibility of the Theobroma cacao and Arabidopsis FT orthologs: 90 million years of functional conservation of meristem identity genes

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
S. F. Prewitt ◽  
A. Shalit-Kaneh ◽  
S. N. Maximova ◽  
M. J. Guiltinan
Keyword(s):  
Gene Expression ◽  
Tissue Culture ◽  
Gene Family ◽  
Flowering Time ◽  
Molecular Mechanisms ◽  
Regulatory Pathways ◽  
Late Flowering ◽  
Precocious Flowering ◽  
Transition To Flowering

Abstract Background In angiosperms the transition to flowering is controlled by a complex set of interacting networks integrating a range of developmental, physiological, and environmental factors optimizing transition time for maximal reproductive efficiency. The molecular mechanisms comprising these networks have been partially characterized and include both transcriptional and post-transcriptional regulatory pathways. Florigen, encoded by FLOWERING LOCUS T (FT) orthologs, is a conserved central integrator of several flowering time regulatory pathways. To characterize the molecular mechanisms involved in controlling cacao flowering time, we have characterized a cacao candidate florigen gene, TcFLOWERING LOCUS T (TcFT). Understanding how this conserved flowering time regulator affects cacao plant’s transition to flowering could lead to strategies to accelerate cacao breeding. Results BLAST searches of cacao genome reference assemblies identified seven candidate members of the CENTRORADIALIS/TERMINAL FLOWER1/SELF PRUNING gene family including a single florigen candidate. cDNA encoding the predicted cacao florigen was cloned and functionally tested by transgenic genetic complementation in the Arabidopsis ft-10 mutant. Transgenic expression of the candidate TcFT cDNA in late flowering Arabidopsis ft-10 partially rescues the mutant to wild-type flowering time. Gene expression studies reveal that TcFT is spatially and temporally expressed in a manner similar to that found in Arabidopsis, specifically, TcFT mRNA is shown to be both developmentally and diurnally regulated in leaves and is most abundant in floral tissues. Finally, to test interspecies compatibility of florigens, we transformed cacao tissues with AtFT resulting in the remarkable formation of flowers in tissue culture. The morphology of these in vitro flowers is normal, and they produce pollen that germinates in vitro with high rates. Conclusion We have identified the cacao CETS gene family, central to developmental regulation in angiosperms. The role of the cacao’s single FT-like gene (TcFT) as a general regulator of determinate growth in cacao was demonstrated by functional complementation of Arabidopsis ft-10 late-flowering mutant and through gene expression analysis. In addition, overexpression of AtFT in cacao resulted in precocious flowering in cacao tissue culture demonstrating the highly conserved function of FT and the mechanisms controlling flowering in cacao.

Distinctive IgVH Gene Segments Usage and Mutation Status in Chinese Patients with Chronic Lymphocytic Leukemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4708-4708
Author(s):  
Lijuan Chen ◽  
Yaping Zhang ◽  
Wenjuuan Zheng ◽  
Jianyong Li ◽  
Changgeng Ruan
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Gene Family ◽  
Gene Families ◽  
Lymphocytic Leukemia ◽  
Chinese Patients ◽  
Chain Gene ◽  
Mutation Status ◽  
Significant Difference ◽  
Variable Heavy ◽  
Vh Gene

Abstract Chronic lymphocytic leukemia (CLL) is characterized by the relentless accumulation of monoclonal B cells with the appearance of small mature lymphocytes and a characteristic CD5 and CD19 co-expression immunophenotype. The incidence of CLL in Asian countries is lower than that in the Western ones, where CLL is the most common leukemia. To evaluate the frequency and mutation status of immunoglobulin (Ig) variable heavy chain gene (IgVH) expression in Chinese patients with CLL. We investigated IgVH gene segments usage and mutation status by multiplex RT-PCR in 52 CLL patients, and analyzed the relationship between IgVH somatic mutation status and the expression of CD38, ZAP-70 and CLLU1. 38 patients had mutated IgVH, and 14 had unmutated IgVH. The most frequently expressed VH gene family was found to be VH3 (46.2%) followed by VH4 (40.4%), VH1 (5.8%), VH2 (5.8%) and VH7 (1.9%), with no expression of VH5 and VH6 gene families. VH1-69 and VH3-21 which commonly overused in Western CLL weren’t detected in our cohort. The frequency of IgVH gene families indicates significant difference in Chinese CLL patients compared with Western patients, suggesting involvement of ethnic and/or environmental factors in CLL disease initiation. IgVH gene mutation status was significantly associated with the expression of CD38 and CLLU1. The expression of them may be simple and reliable surrogates for the identification of IgVH mutations. VH gene family usage and mutation status VH family n Mutated VH gene Unmutated VH gene VH1 3 3 0 VH2 3 2 1 VH3 24 19 5 VH4 21 16 5 VH5 0 0 0 VH6 0 0 0 VH7 1 0 1

scholarly journals Transcription Profiles Associated with Inducible Adhesion in Candida parapsilosis

mSphere ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Joseph M. Bliss ◽  
George A. Tollefson ◽  
Abigail Cuevas ◽  
Sarah J. Longley ◽  
Matthew N. Neale ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Family ◽  
Candida Parapsilosis ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Enrichment Analysis ◽  
Gene Families ◽  
Mammalian Host ◽  
Emerging Infections ◽  
Content Type

ABSTRACT Candida parapsilosis has emerged as a frequent cause of invasive candidiasis with increasing evidence of unique biological features relative to C. albicans. As it adapts to conditions within a mammalian host, rapid changes in gene expression are necessary to facilitate colonization and persistence in this environment. Adhesion of the organism to biological surfaces is a key first step in this process and is the focus of this study. Building on previous observations showing the importance of a member of the ALS gene family in C. parapsilosis adhesion, three clinical isolates were cultured under two conditions that mimic the mammalian host and promote adhesion, incubation at 37°C in tissue culture medium 199 or in human plasma. Transcriptional profiles using RNA-seq were obtained in these adhesion-inducing conditions and compared to profiles following growth in yeast media that suppress adhesion to identify gene expression profiles associated with adhesion. Overall gene expression profiles among the three strains were similar in both adhesion-inducing conditions and distinct from adhesion-suppressing conditions. Pairwise analysis among the three growth conditions identified 133 genes that were differentially expressed at a cutoff of ±4-fold, with the most upregulated genes significantly enriched in iron acquisition and transmembrane transport, while the most downregulated genes were enriched in oxidation-reduction processes. Gene family enrichment analysis identified gene families with diverse functions that may have an important role in this important step for colonization and disease. IMPORTANCE Invasive Candida infections are frequent complications of the immunocompromised and are associated with substantive morbidity and mortality. Although C. albicans is the best-studied species, emerging infections by non-albicans Candida species have led to increased efforts to understand aspects of their pathogenesis that are unique from C. albicans. C. parapsilosis is a frequent cause of invasive infections, particularly among premature infants. Recent efforts have identified important virulence mechanisms that have features distinct from C. albicans. C. parapsilosis can exist outside a host environment and therefore requires rapid modifications when it encounters a mammalian host to prevent its clearance. An important first step in the process is adhesion to host surfaces. This work takes a global, nonbiased approach to investigate broad changes in gene expression that accompany efficient adhesion. As such, biological pathways and individual protein targets are identified that may be amenable to manipulation to reduce colonization and disease from this organism.

scholarly journals Differential expression of VH gene families in peripheral B cell repertoires of newborn or adult immunoglobulin H chain congenic mice.

1992 ◽  
Vol 175 (6) ◽  
pp. 1449-1456 ◽  
Author(s):  
A C Viale ◽  
A Coutinho ◽  
A A Freitas
Keyword(s):  
Gene Family ◽  
B Cell ◽  
Expression Pattern ◽  
Gene Families ◽  
Cell Repertoire ◽  
Adult Mice ◽  
Igh Locus ◽  
B Cell Repertoire ◽  
Vh Gene ◽  
Old Mice

The pattern of VH gene family expression in the primary B cell repertoire of the mouse is strain dependent. In C57Bl/6 mice, the VH J558 family is expressed by more than 45% of the cells, while the expression of VH 7183, VH Q52, and VH 36-60 families together does not exceed 20%. In BALB/c mice, relative expression of VH J558 is lower than 35%, while the sum of the other three families reaches 25%. To assess which genetic loci control strain-specific VH gene family expression, we studied VH gene family usage in splenic B cell repertoires of different congenic strains of mice. Changes in major histocompatibility complex or immunoglobulin (Ig) K light chain genes did not modify VH gene family expression in adult mice. Differences at the IgH locus, however, modified VH gene family usage. In 1-d-old mice, the strain-specific VH gene family expression pattern is determined by the IgH haplotype. In adult mice, the VH gene family expression pattern of resting B cells is independent of the IgH locus and follows the genetic background of the congenic strain, while it is determined by the IgH haplotype among Ig-secreting spleen cells. In F1(B6 x BALB/c) mice, each of the two spleen B cell populations, sorted on the basis of mu heavy chain allotype expression, shows an independent VH gene family expression pattern, determined by the IgH locus. The implications of these results in the control of VH gene family expression, and in the selection of peripheral B cell repertoires are discussed.

scholarly journals VH gene family expression in mice with the xid defect.

1991 ◽  
Vol 174 (1) ◽  
pp. 45-51 ◽  
Author(s):  
S H Feng ◽  
K E Stein
Keyword(s):  
Gene Family ◽  
Gene Families ◽  
Gene Defect ◽  
X Chromosomes ◽  
Polysaccharide Antigens ◽  
Specific Antigens ◽  
Vh Gene ◽  
Vh Genes ◽  
Predominant Expression

Preferential use of particular VH gene families in the response to specific antigens has been demonstrated in several systems. The lack of responses to certain types of antigens, therefore, could be the result of deletion of or failure to express some VH genes. Because CBA/N mice, which carry the X-linked immunodeficiency (xid) gene defect, have been shown to be unresponsive to thymus-independent polysaccharide antigens, it was of interest to examine if this unresponsiveness could be accounted for by abnormal expression of particular VH gene families. Using in situ hybridization on B cell colonies, we determined the expression of nine VH gene families in CBA/CaHN females (genotypically normal), CBA/N males (xid) and females (xid), and (CBA/N x CBA/CaHN)F1 males (xid) and females (phenotypically normal). Our results indicate that VH gene family expression, including the S107 family, in CBA/N males and F1 males, is similar to that of CBA/CaHN and F1 females with predominant expression of J558, the largest gene family, in all individuals. Interestingly, CBA/N female mice, which carry two defective X chromosomes, as a group expressed significantly reduced levels of the J558 gene family, and as individuals showed variation in which family was predominantly expressed. We conclude that the unresponsiveness of mice with the xid defect to polysaccharide antigens can not attributed to a failure to express the nine VH gene families that we examined. Our findings do not support previous studies (Primi, D., and P.-A. Cazenave 1986. J. Exp. Med. 165:357), which found an absence of expression of the S107 family in xid mice.

scholarly journals Comparison of the fetal and adult functional B cell repertoires by analysis of VH gene family expression.

1988 ◽  
Vol 168 (2) ◽  
pp. 589-603 ◽  
Author(s):  
H D Jeong ◽  
J M Teale
Keyword(s):  
Gene Expression ◽  
In Situ Hybridization ◽  
B Cells ◽  
Gene Family ◽  
B Cell ◽  
Cell Lineage ◽  
Cell Repertoire ◽  
B Cell Repertoire ◽  
Vh Gene

The functional B cell repertoire in BALB/c mice was assessed at various stages in ontogeny. This was done by analyzing VH gene family expression using the sensitive technique of in situ hybridization. The B cell repertoire was probed with the mitogen, LPS, and the antigen DNP. DNP was chosen because B cells responsive to this hapten appear very early in ontogeny. The APCs that developed after stimulation with LPS or DNP were analyzed for VH gene expression by in situ hybridization of individual cells using radiolabeled VH gene family probes. The results indicated that VH gene expression in fetal B cells after stimulation was distinct from adult B cells in that there was a biased expression of D proximal families. The results indicated that this bias was associated with developmental age and not a given differentiation stage in the B cell lineage. In addition, stimulation of fetal B cells with DNP resulted in a large increase in expression of member(s) of VH 36-60, suggesting that the early appearance of DNP-responsive B cells is not strictly correlated with preferential rearrangement of D proximal families, VH 7183 and VH Q52. However, the results suggested that a large proportion of pre-B cells that preferentially rearrange D proximal families early in ontogeny become part of the functional developing repertoire.

scholarly journals Host plant adaptation in the polyphagous whitefly, Trialeurodes vaporariorum, is associated with transcriptional plasticity and altered sensitivity to insecticides

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Adam Pym ◽  
Kumar Saurabh Singh ◽  
Åsa Nordgren ◽  
T. G. Emyr Davies ◽  
Christoph T. Zimmer ◽  
...  
Keyword(s):  
Gene Expression ◽  
Host Plants ◽  
Large Scale ◽  
Molecular Mechanisms ◽  
Wide Spectrum ◽  
Transcriptome Profiling ◽  
Gene Families ◽  
Trialeurodes Vaporariorum ◽  
Specific Gene ◽  
Natural And Synthetic

Abstract Background The glasshouse whitefly, Trialeurodes vaporariorum, is a damaging crop pest and an invasive generalist capable of feeding on a broad range of host plants. As such this species has evolved mechanisms to circumvent the wide spectrum of anti-herbivore allelochemicals produced by its host range. T. vaporariorum has also demonstrated a remarkable ability to evolve resistance to many of the synthetic insecticides used for control. Results To gain insight into the molecular mechanisms that underpin the polyphagy of T. vaporariorum and its resistance to natural and synthetic xenobiotics, we sequenced and assembled a reference genome for this species. Curation of genes putatively involved in the detoxification of natural and synthetic xenobiotics revealed a marked reduction in specific gene families between this species and another generalist whitefly, Bemisia tabaci. Transcriptome profiling of T. vaporariorum upon transfer to a range of different host plants revealed profound differences in the transcriptional response to more or less challenging hosts. Large scale changes in gene expression (> 20% of genes) were observed during adaptation to challenging hosts with a range of genes involved in gene regulation, signalling, and detoxification differentially expressed. Remarkably, these changes in gene expression were associated with significant shifts in the tolerance of host-adapted T. vaporariorum lines to natural and synthetic insecticides. Conclusions Our findings provide further insights into the ability of polyphagous insects to extensively reprogram gene expression during host adaptation and illustrate the potential implications of this on their sensitivity to synthetic insecticides.

scholarly journals Ig VH gene expression among human follicular lymphomas

Blood ◽  
1991 ◽  
Vol 78 (6) ◽  
pp. 1561-1568 ◽  
Author(s):  
DW Bahler ◽  
MJ Campbell ◽  
S Hart ◽  
RA Miller ◽  
S Levy ◽  
...  
Keyword(s):  
Gene Expression ◽  
Variable Region ◽  
Gene Families ◽  
Peripheral Blood Lymphocytes ◽  
Low Grade ◽  
Normal Peripheral Blood ◽  
Germline Genes ◽  
Vh Gene ◽  
Vh Genes ◽  
Follicular Lymphomas

Abstract Thirty-six randomly selected cases of low grade follicular lymphoma (FL) were analyzed for Ig heavy chain variable region (VH) gene expression. Assignment to one of the six human VH gene families (VH1 to VH6) was made with a polymerase chain reaction-based technique using family-specific leader primers. The frequency of VH family use in FL was found to be similar to that reported for normal peripheral blood lymphocytes and is therefore also roughly proportional to VH family size. To evaluate expression within an individual family, all of the lymphoma VH genes from the middle size VH4 family were sequenced and compared with previously published sequences. Of these eight lymphoma VH sequences, six were most closely related to just two of the 10 known functional VH4 germline genes. Nonrandom usage by FL of the JH3, JH4, and JH5 joining segments was also observed. Nucleotide sequences were also determined for 10 randomly selected lymphoma VH genes from the large VH3 family. With one possible exception, none of these lymphoma VH sequences appear to represent any of the VH3 genes that may be preferentially used in the fetal repertoire.

scholarly journals The organization of the mouse Igh-V locus. Dispersion, interspersion, and the evolution of VH gene family clusters.

1988 ◽  
Vol 168 (6) ◽  
pp. 2261-2278 ◽  
Author(s):  
P H Brodeur ◽  
G E Osman ◽  
J J Mackle ◽  
T M Lalor
Keyword(s):  
Gene Family ◽  
Leukemia Virus ◽  
Gene Families ◽  
Functional Expression ◽  
Gene Deletions ◽  
Group Members ◽  
Vh Gene ◽  
Abelson Murine Leukemia Virus ◽  
Relationship Of ◽  
The Relationship

We have constructed a panel of Abelson murine leukemia virus-transformed pre-B cells to study the organization of the mouse VH gene families. Based on the analyses of VH gene deletions on 51 chromosomes with VH gene rearrangements, we have inferred a map order of the Igh locus that holds for both the Igha and Ighb haplotypes. We show that members of each VH gene family are generally clustered, although three family clusters (VHS107, VH36-60, VGAM3.8) are dispersed in two or three subregions of the locus. Members of two VH gene families, VHQ52 and VH7183, are extensively interspersed and map within the same subregion. An examination of the distribution of VH group members (VH II, I, and III) within the locus suggests that two major duplications may, in part, explain the dispersed pattern of VH family clusters. The relationship of VH organization and functional expression is discussed in terms of position-dependent and complexity-driven models.

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