• Animal cells and systems
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• 제1권4호
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• pp.629-635
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• 1997

Previously we reported the migration and rearrangement of a chloroplast gene cluster into mitochondria. The exact genomic locations of the clusters, modes of the gene rearrangement and mechanisms of the interorganellar migration of the clusters have yet to be understood. The detailed analysis needs to include a larger region of DNA surrounding each cluster. To study DNA rearrangement and migration in more detail a cosmid library was constructed using the total rice genomic DNA including nuclear, chloroplast and mitochondrial DNA. From this cosmid library, a sub-library was obtained by selecting the clones hybridized to various regions of chloroplast DNA. According to the hybridization pattern 136 clones from the sub-library were classified into 29 groups. Detailed analysis of these clones revealed that in addition to authentic chloroplast DNA, the clones contain its homologs resulted from rearrangement and mutation. We analyzed two clones in detail, which contain different rp12 homologs resulted from rearrangement and/or migration, respectively.

• Applied Biological Chemistry
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• 제36권3호
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• pp.208-214
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• 1993

엽록체 DNA 내에서 반복 염기서열의 존재와 이들에 의한 유전자 재배열 현상을 고찰하기 위하여 151bp Repeated Sequence 갖는 이질적인 유전인자군의 존재를 여러가지 품종의 벼 엽록체 DNA에서 관찰 하였다. 또한 쌀 DNA를 벼의 생장과 조직부위에 따라 분리하고, rp12 probe를 이용하여 Southern blot 분석하여 엽록체의 발달에 따르는 엽록체 DNA의 재배열 현상을 관찰하였다. 아울러 유전자 재배열 현상을 유발하는 반복염기서열을 database로부터 검색하여 유전자의 상호 비교 분석하였다. 그 결과 151bp Repeated Sequence와 유사한 염기 서열을 같는 rp123유전자를 포함하는 이질적인 유전인자군은 어느 특정한 품종의 벼에 국한되는것이 아니고 본 실험에 사용된 다양한 품종의 벼에 일반적으로 나타나는 현상임이 확인되었으며 또한 이들의 양상은 벼의 조직 부위에 따라 다르게 나타나고 있음을 확인하였다. 이러한 실험적 결과와 함께 엽록체 유전자 database의 검색과 유전자의 상호비교분석을 통하여 151bp 반복 염기 저열에 의한 벼 엽록체 DNA의 유전자 재배열현상은 식물 특히 단자엽 식물의 진화와 함께 발달된 현상으로 특히 151bp반복 염기 서열은 매우 다양한 유전자 재배열을 유발하는 변이유발 위치로 발달되어 왔음을 확인할 수 있었다. 따라서 이러한 반복염기서열에 의한 유전자 재배열 현상은 특히 벼에 있어서 plastid의 발달에 밀접하게 관여하고 있음을 제시하고 있다.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.391-401
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• 1987

Plant chloroplast DNA exists as an unique circular structure in which large single copy(LSC) region and small single copy (SSC) region are separated by large inverted repeat sequences (IRS). It has been known that the unique existence of inverted repeat sequences in chloroplast DNA has no relation with the stability of the chloroplast DNA, but causes the inversion between inverted repeat its biological significance has not been understood so far. In rice, several gene clusters have been cloned and sequenced which contain ribulose-5-biophosphate car-boxylase large subunit (rbcL). Especially, one rbcL gene is linked with rp12 gene which is located in the IRS region in one of the gene clusters. By comparison of nucleotide sequence, the two genes are found to be linked through 151 bp repeat sequence which is homologous to the rp123 gene in IRS region. The repeat sequence is found to be located 3' downstream of rfcL gene and near psbA gene in LSC region. The existence of these repeat sequences and the presence of gene clusters caused by the gene rearrangement thorough the repeat sequence provide a possible which is found to be dispersed chloroplast DNA provide the model system to explaine the heterogeneity of the chloroplast DNA in rice in term of gene rearrangement.

• IMMUNE NETWORK
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• 제2권2호
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• pp.79-85
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• 2002

Background: In contrast to evidences of Ig H chain receptor editing in transformed cell lines and transgenic mouse models, there has been no direct evidence that this phenomenon occurs in human developing B cells. Methods: $V_HDJ_H$ rearrangements were obtained from genomic DNA of individual $IgM^-$ B cells from liver and $IgM^+B$ cells from bone marrow of 18 wk of gestation human fetus by PCR amplification and direct sequencing. Results: We found three examples of H chain receptor editing from $IgM^+$ and $IgM^-human$ fetal B cells. Two types of $V_H$ replacements were identified. The first involved $V_H$ hybrid formation, in which part of a $V_H$ gene from the initial VDJ rearrangement is replaced by part of an upstream $V_H$ gene at the site of cryptic RSS. The second involved a gene conversion like replacement of CDR2, in which another $V_H$ gene donated a portion of its CDR2 sequence to the initial VDJ rearrangement. Conclusion: These data provide evidence of receptor editing at the H chain loci in developing human B cells, and also the first evidence of a gene conversion event in human Ig genes.

• Molecules and Cells
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• 제43권5호
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• pp.448-458
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• 2020

T-DNA insertional mutations in Arabidopsis genes have conferred huge benefits to the research community, greatly facilitating gene function analyses. However, the insertion process can cause chromosomal rearrangements. Here, we show an example of a likely rearrangement following T-DNA insertion in the Anti-Silencing Function 1B (ASF1B) gene locus on Arabidopsis chromosome 5, so that the phenotype was not relevant to the gene of interest, ASF1B. ASF1 is a histone H3/H4 chaperone involved in chromatin remodeling in the sporophyte and during reproduction. Plants that were homozygous for mutant alleles asf1a or asf1b were developmentally normal. However, following self-fertilization of double heterozygotes (ASF1A/asf1a ASF1B/asf1b, hereafter AaBb), defects were visible in both male and female gametes. Half of the AaBb and aaBb ovules displayed arrested embryo sacs with functional megaspore identity. Similarly, half of the AaBb and aaBb pollen grains showed centromere defects, resulting in pollen abortion at the bi-cellular stage of the male gametophyte. However, inheritance of the mutant allele in a given gamete did not solely determine the abortion phenotype. Introducing functional ASF1B failed to rescue the AaBb- and aaBb-mediated abortion, suggesting that heterozygosity in the ASF1B gene causes gametophytic defects, rather than the loss of ASF1. The presence of reproductive defects in heterozygous mutants but not in homozygotes, and the characteristic all-or-nothing pollen viability within tetrads, were both indicative of commonly-observed T-DNA-mediated translocation activity for this allele. Our observations reinforce the importance of complementation tests in assigning gene function using reverse genetics.

• 미생물학회지
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• 제28권3호
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• pp.219-228
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• 1990

자연계로부터 분리한 DK1 균주(NI)가 가지고 있는 $Km^r$ plasmid를 유전자조작 기법으로 변형시킨 DKC601 균주 (GEM)를 이용하여 $Km^r$ 유전자의 전이를 무심천의 자연 수계환경에서 실험하였다. $Km^r$ 유전자의 전이 빈도는 NI 균주의 결과와 비교 연구하는 동시에, 전이과정에서 일어나는 plasmid rearrangement를 비교 분석하였다. GEM과 NI의 $Km^r$ 유전자의 전이 빈도는 5-$10^{\circ}C$의 하천수에서는 $9.1\times 10^{-12}~1.8\times 10^{-11}$로 비슷하였으나 20-$30^{\circ}C$에서는 NI 균주가 GEM 균주보다 조금 높았다. 그리고 멸균하천수나 LB broth를 이용한 실험실 환경에서의 $Km^r$ 유전자의 전이 빈도는 하천수에서 보다 다소 높게 나타났다. NI 균주가 가지고 있던 70kb인 $Km^r$ plasmid는 MTl 균주를 recipient로 했을 때에 얻은 transconjugant에서는 수계환경에 관계없이 rearrangement가 많이 일어났으나, GEM 균주에서 얻은 transconJug gant에서는 52 kb인 $Km^r$ plasmid가 안정된 상태로 발견되었다. 그러나 MT2 균주들 recipient로 했을 때에는 NI 뿐만 아니라 GEM 균주로부터 전이된 $Km^r$ plasmid가 모두 rearrangement를 나타냈다. Transconjugant들이 가지고 있는 plasmid의 수는 conjugation의 시간이 길어짐에 따라 사용한 성험균주나 수계환경에 관계없이 감소되었으며, 특히 GEM의 5 52 kb인 $Km^r$ 유전자의 크기는 24시간 후에도 그대로 유지되였다. 이와 같은 결과로 볼 때, $Km^r$ 유전자는 GEM에서나 NI로부터 전이되는 빈도는 recipient 균주에 관계없이 비슷하였으나, conjugation 과정 중 GEM의 $Km^r$ 유전자는 NI의 $Km^r$ 유전자보다 더욱 안정된 상태로 전이되었으며 이 $Km^r$ plasmid의 rearrangement는 수계환경에 관계없이 recipient 균주에 따라 다양하게 나타났다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.346.1-346
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• 1995

No Abstract, See Full Text

• BMB Reports
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• 제29권3호
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• pp.241-247
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• 1996

The Philadelphia (Ph) chromosome is the single most intensively studied chromosome alteration characterizing a human malignancy. The specific genetic alteration of chronic myelogenous leukemia (CML) is the formation of the BCR/abl fusion gene in leukemic cells. The presence of the BCR/abl gene has important diagnostic and prognostic implications in CML. The detection of BCR/abl transcripts by reverse transcriptase based polymerase chain reaction (RT-PCR) was investigated in patients with CML in whom the Ph chromosome abnormality was documented by cytogenetic analysis. In a total of 68 CML patient cases, the Ph chromosome was found in 53 cases (77.9%) by cytogenetic analysis. On the other hand, sixty two cases (91.2%) were detected to have BCR/abl gene rearrangement Of these, b3a2 was 44 cases (64.7%) and b2a2 was 17 cases (25,0%). There was one case with both b3a2 and b2a2 (1.5%). Of the fifteen cases of Ph chromosome negative by cytogenetic anlaysis, the BCR/abl gene was observed in nine cases, The results of BCR/abl fusion gene confirmed by the direct sequencing method correlated well with PCR analysis, The amplified PCR products were detected by $1{\times}10^{-5}$ dilutions. In conclusion, PCR technique is sensitive, rapid and relatively simple for a laboratory test in detecting the BCR/abl fusion gene with CML regardless of the result of cytogenetic analysis.

• BMB Reports
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• 제46권6호
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• pp.310-315
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• 2013

The gene order on the X chromosome of eutherians is generally highly conserved, although an increase in the rate of rearrangement has been reported in the rodent lineage. Conservation of the X chromosome is thought to be caused by selection related to maintenance of dosage compensation. However, we herein reveal that the cattle (Btau4.0) lineage has experienced a strong increase in the rate of X-chromosome rearrangement, much stronger than that previously reported for rodents. We also show that this increase is not matched by a similar increase on the autosomes and cannot be explained by assembly errors. Furthermore, we compared the difference in two cattle genome assemblies: Btau4.0 and Btau6.0 (Bos taurus UMD3.1). The results showed a discrepancy between Btau4.0 and Btau6.0 cattle assembly version data, and we believe that Btau6.0 cattle assembly version data are not more reliable than Btau4.0.

• 한국임상수의학회지
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• 제26권5호
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• pp.419-422
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• 2009

개의 림프종을 분자유전자학적으로 진단하고자 본 연구를 수행하였다. 이를 위하여 12개의 염색 및 고정된 도말 표본으로부터 DNA를 추출한 후, 임파육종에 특이적인 재배열된 항원 수용체 유전자를 중합효소연쇄반응으로 증폭시켰다. 그 결과 6개의 type-B 림프종에서 type-B 세포의 림프종에 특이적인 IgH (immunoglobulin H) 주유전자(major gene)와 type-B 림프종의 부유전자(minor gene)가 증폭되었다. 또한, 3개의 type-T 세포의 림프종의 경우에도 이에 특이적인 $TCR{\gamma}$ 유전자가 증폭되었다. 한편, 에를리키아증에 이환된 표본은 $TCR{\gamma}$ 유전자가 위양성으로 증폭되었지만, 활성화된 림프절 샘플의 경우에는 어떤 유전자의 재배열도 관찰되지 않았다. 따라서 림프종의 진단에 있어서 혈액 또는 조직 도말 표본의 DNA를 이용하여 재배열된 항원 수용체 유전자의 검출을 시도한다면, 특이적이고 객관적으로 림프종을 감별진단 할 수 있을 것이며, 나아가 회고적 분석에도 유용하게 활용될 수 있을 것으로 사료된다.