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PubMed2003

Expressed sequence tags from a wheat-rye translocation line (2BS/2RL) infested by larvae of Hessian fly [Mayetiola destructor (Say)].

Of the 16 known biotypes of the Hessian fly [ Mayetiola destructor (Say)], biotype L is recognized as being the most virulent. We have previously reported the development of near-isogenic lines (NILs) (BC(3)F(3:4)) by backcross introgression (Coker797*4/Hamlet) that differed by the presence or absence of the H21 gene on 2RL chromatin. Florescence in situ hybridization analysis revealed introgressed 2RLs in NILs possessing the H21 gene, but no signal was detected in NILs lacking 2RL. As part of an approach to elucidate molecular interactions between plants and the Hessian fly, a cDNA library from NILs with H21 infested by larvae of biotype L of the Hessian fly was constructed for expressed sequence tag (EST) analysis. Of 1,056 sequenced reactions attempted, 919 ESTs produced some lengths of readable sequences. Based on their putative identification, 730 ESTs that showed significant similarity with amino acid sequences registered in the gene bank were divided into 13 functional categories. Defense- and stress-related genes represented about 16.1%, including protease inhibition, oxidative burst, lignin synthesis, and phenylpropanoid metabolism. EST clones obtained from the cDNA library may provide a clue to the molecular interactions between plant and larva of the Hessian fly larval infestation.

Animals↗

PubMed2006

Analysis and functional annotation of expressed sequence tags from the fall armyworm Spodoptera frugiperda.

BACKGROUND: Little is known about the genome sequences of lepidopteran insects, although this group of insects has been studied extensively in the fields of endocrinology, development, immunity, and pathogen-host interactions. In addition, cell lines derived from Spodoptera frugiperda and other lepidopteran insects are routinely used for baculovirus foreign gene expression. This study reports the results of an expressed sequence tag (EST) sequencing project in cells from the lepidopteran insect S. frugiperda, the fall armyworm. RESULTS: We have constructed an EST database using two cDNA libraries from the S. frugiperda-derived cell line, SF-21. The database consists of 2,367 ESTs which were assembled into 244 contigs and 951 singlets for a total of 1,195 unique sequences. CONCLUSION: S. frugiperda is an agriculturally important pest insect and genomic information will be instrumental for establishing initial transcriptional profiling and gene function studies, and for obtaining information about genes manipulated during infections by insect pathogens such as baculoviruses.

Animals↗

PubMed1999

Analysis of cDNAs expressed during first cell division of petunia petal protoplast cultures using expressed sequence tags.

A large-scale sequence analysis of randomly selected cDNA clones was performed to isolate numerous genes in petunia petal protoplast cultures. We have partially sequenced 1158 randomly selected genes of the cDNA library constructed from 2-6 d cultured petal protoplasts. Three hundred and sixty-five different genes were identified, 25% of which showed significant similarity to existing sequences in the petunia, and an array of other organisms. In this report, 90 independent genes are analyzed in detail. A functional categorization of the database-matched expressed sequence tags (ESTs) showed that defense- or stress-related genes, as well as genes involved in the primary metabolic pathways and in the transcriptional or translational apparatus are abundantly represented. In particular, ESTs were identified with apparent homologies to the cyclin-dependent kinase, histone, actin-depolymerizing factor, proteasome, and ubiquitin which are expected to be related to cell division or to cell cycle control.

Cell Division↗

PubMed2005

An expressed sequence tag SSR map of tetraploid alfalfa (Medicago sativa L.).

A genetic map constructed from a population segregating for a trait of interest is required for QTL identification. The goal of this study was to construct a molecular map of tetraploid alfalfa (Medicago sativa.) using simple sequence repeat (SSR) markers derived primarily from expressed sequence tags (ESTs) and bacterial artificial chromosome (BAC) inserts of M. truncatula. This map will be used for the identification of drought tolerance QTL in alfalfa. Two first generation backcross populations were constructed from a cross between a water-use efficient, M. sativa subsp. falcata genotype and a low water-use efficient M. sativa subsp. sativa genotype. The two parents and their F(1) were screened with 1,680 primer pairs designed to amplify SSRs, and 605 single dose alleles (SDAs) were amplified. In the F(1), 351 SDAs from 256 loci were mapped to 41 linkage groups. SDAs not inherited by the F(1), but transmitted through the recurrent parents and segregating in the backcross populations, were mapped to 43 linkage groups, and 44 of these loci were incorporated into the composite maps. Homologous linkage groups were joined to form eight composite linkage groups representing the eight chromosomes of M. sativa. The composite maps consist of eight composite linkage groups with 243 SDAs from M. truncatula EST sequences, 38 SDAs from M. truncatula BAC clone sequences, and five SDAs from alfalfa genomic SSRs. The total composite map length is 624 cM, with average marker density per composite linkage group ranging from 1.5 to 4.4 cM, and an overall average density of 2.2 cM. Segregation distortion was 10%, and distorted loci tended to cluster on individual homologues of several linkage groups.

Chromosome Mapping↗

PubMed2004

Developmental expression of 2489 gene clusters during pig embryogenesis: an expressed sequence tag project.

Identification of mRNAs that are present at early stages of embryogenesis is critical for a better understanding of development. To this end, cDNA libraries were constructed from germinal vesicle-stage oocytes, in vivo-produced four-cell- and blastocyst-stage embryos, and from in vitro-produced four-cell- and blastocyst-stage embryos. Randomly picked clones (10 848) were sequenced from the 3' end and those of sufficient quality (8066, 74%) were clustered into groups of sequence similarity (>95% identity), resulting in 2489 clusters. The sequence of the longest representative expressed sequence tag (EST) of each cluster was compared with GenBank and TIGR. Scores below 200 were considered unique, and 1114 (44.8%) did not have a match in either database. Sequencing from the 5' end yielded 12 of 37 useful annotations, suggesting that one third of the 1114 might be identifiable, still leaving over 700 unique ESTs. Virtual Northerns compared between the stages identified numerous genes where expression appears to change from the germinal vesicle oocyte to the four-cell stage, from the four-cell to blastocyst stage, and between in vitro- and in vivo-derived four-cell- and blastocyst-stage embryos. This is the first large-scale sequencing project on early pig embryogenesis and has resulted in the discovery of a large number of genes as well as possible stage-specific expression. Because many of these ESTs appear to not be in the public databases, their addition will be useful for transcriptional profiling experiments conducted on early pig embryos.

Animals↗

PubMed2001

Immune gene discovery by expressed sequence tag analysis of hemocytes and hepatopancreas in the Pacific White Shrimp, Litopenaeus vannamei, and the Atlantic White Shrimp, L. setiferus.

A pilot program was undertaken in immune gene discovery in two sister species of litopenaeid shrimp, the Pacific white shrimp, Litopenaeus vannamei and the Atlantic white shrimp, L. setiferus. RNA from the hemocytes and hepatopancreas of single individuals from each species was recovered, 4 cDNA libraries (one from each tissue/species) were made by a PCR-based method and a total of approximately 2045 randomly selected clones were sequenced. A total of 268 expressed sequence tags (ESTs) were found that corresponded to 44 immune function genes. The most common immune-function ESTs (172) were antimicrobial peptides, which were restricted to the hemocyte libraries. Lectins were the largest group of immune-function ESTs found in the hepatopancreas. Analysis of these libraries indicates that EST approaches are effective for immune gene discovery in shrimp and that the diversity of these PCR-generated libraries would support full-scale EST collection.

Animals↗

PubMed2004

High-throughput peptide mass fingerprinting of soybean seed proteins: automated workflow and utility of UniGene expressed sequence tag databases for protein identification.

Identification of anonymous proteins from two-dimensional (2-D) gels by peptide mass fingerprinting is one area of proteomics that can greatly benefit from a simple, automated workflow to minimize sample contamination and facilitate high-throughput sample processing. In this investigation we outline a workflow employing robotic automation at each step subsequent to 2-D gel electrophoresis. As proof-of-concept, 96 protein spots from a 2-D gel were analyzed using this approach. Whole protein (1 mg) from mature, dry soybean (Glycine max [L.] Merr.) cv. Jefferson seed was resolved by high resolution 2-D gel electrophoresis. Approximately 150 proteins were observed after staining with Coomassie Blue. The rather low number of detected proteins was due to the fact that the dynamic range of protein expression was greater than 100-fold. The most abundant proteins were seed storage proteins which in total represented over 60% of soybean seed protein. Using peptide mass fingerprinting 44 protein spots were identified. Identification of soybean proteins was greatly aided by the use of annotated, contiguous Expressed Sequence Tag (EST) databases which are available for public access (UniGene, ftp.ncbi.nih.gov/repository/UniGene/). Searches were orders of magnitude faster when compared to searches of unannotated EST databases and resulted in a higher frequency of valid, high-scoring matches. Some abundant, non seed storage proteins identified in this investigation include an isoelectric series of sucrose binding proteins, alcohol dehydrogenase and seed maturation proteins. This survey of anonymous seed proteins will serve as the basis for future comparative analysis of seed-filling in soybean as well as comparisons with other soybean varieties.

Databases, Genetic↗

PubMed2004

An Ambystoma mexicanum EST sequencing project: analysis of 17,352 expressed sequence tags from embryonic and regenerating blastema cDNA libraries.

BACKGROUND: The ambystomatid salamander, Ambystoma mexicanum (axolotl), is an important model organism in evolutionary and regeneration research but relatively little sequence information has so far been available. This is a major limitation for molecular studies on caudate development, regeneration and evolution. To address this lack of sequence information we have generated an expressed sequence tag (EST) database for A. mexicanum. RESULTS: Two cDNA libraries, one made from stage 18-22 embryos and the other from day-6 regenerating tail blastemas, generated 17,352 sequences. From the sequenced ESTs, 6,377 contigs were assembled that probably represent 25% of the expressed genes in this organism. Sequence comparison revealed significant homology to entries in the NCBI non-redundant database. Further examination of this gene set revealed the presence of genes involved in important cell and developmental processes, including cell proliferation, cell differentiation and cell-cell communication. On the basis of these data, we have performed phylogenetic analysis of key cell-cycle regulators. Interestingly, while cell-cycle proteins such as the cyclin B family display expected evolutionary relationships, the cyclin-dependent kinase inhibitor 1 gene family shows an unusual evolutionary behavior among the amphibians. CONCLUSIONS: Our analysis reveals the importance of a comprehensive sequence set from a representative of the Caudata and illustrates that the EST sequence database is a rich source of molecular, developmental and regeneration studies. To aid in data mining, the ESTs have been organized into an easily searchable database that is freely available online.

Ambystoma↗

PubMed1999

Refinement of the LOH region 1 at 11q23.1 deleted in human breast carcinomas and sublocalization of 11 expressed sequence tags within the refined region.

Loss of constitutive heterozygosity at 11q23 has been detected in various human solid tumors. Here, we described the analysis of a series of normal and tumor pairs from 110 breast carcinomas for the presence of loss of heterozygosity at 11q23 loci. The overall frequency of LOH was 48%, confirming the importance of deletions at 11q23 in breast tumorigenesis. Previously, we have identified two independent regions of LOH at 11q23, the LOH region 1 at 11q23.1 and the LOH region 2 at 11q23.3. The most telomeric region was recently refined between loci D11S1345 and D11S1316, a region of about 1 Mb. However, the LOH region 1, most centromeric, was still not finely refined: the boundaries were defined by loci D11S2000 and D11S897, separated by about 8 Mb. Here, we refined its boundaries between loci D11S1347 and D11S927, a region of about 2 Mb. We have mapped 11 expressed sequence tags (ESTs) within this region and excluded another 20. This study represents a further step toward the identification of the putative tumor suppressor gene found within the LOH region 1 at 11q23.1.

Breast Neoplasms↗

PubMed1998

An expressed-sequence-tag database of the human prostate: sequence analysis of 1168 cDNA clones.

The human prostate is a complex glandular organ with functional development under hormonal regulation. Diseases of the prostate result in significant morbidity and mortality in the form of benign prostatic hypertrophy and prostate adenocarcinoma. The characterization of the molecular framework of the human prostate at the level of expressed genes will facilitate the understanding of normal and pathological prostate biology. The purposes of this study were to acquire an initial assessment of the qualitative and quantitative diversity of gene expression in the normal human prostate and to determine the extent that genes with prostate-restricted expression can be assessed using an expressed sequence tag approach. We have constructed a directional cDNA library from normal adult human prostate tissue and partially sequenced the 5' end of 1168 randomly selected cDNA clones, resulting in more than 400 kb of DNA sequence. Homology searches of the sequenced cDNAs against the GenBank and dbEST databases revealed that 43% of the sequences are identical to human genes whose functions are known, 5% are similar but not identical to known genes in humans or lower organisms, 5% match the mitochondrial genome, 9% are composed of interspersed DNA repeats, 30% are homologous to sequences in the dbEST database without a described function, and 6% are novel sequences. A total of 780 distinct species were identified. In addition to the 74 novel transcripts, 4 genes, prostate-specific antigen (PSA), prostate secretory protein (PSP), prostate acid phosphatase (PAP), and human glandular kallekrein 2 (HK2), have no homologous sequences in the databases that originate from sources other than prostate and thus may represent genes with prostate-restricted expression. Sequences matching PSA, PSP, and PAP each accounted for > 1% of the total ESTs and represent highly abundant transcripts, correlating with the abundance of these proteins in the prostate gland. No novel transcripts were represented by more than one EST and thus are expressed at levels much lower than the known prostate-specific genes.

Adult↗

PubMed2000

Cloning of differentially expressed sequence tags from nickel-transformed human embryonic lung cells.

Differential display polymerase chain reaction (DD-PCR) was used to analyze the differentially expressed genes from nickel-transformed human embryonic lung (HEL) cells (MRC-9 and IMR-90) and their control counterparts (non-treated). Two genes, MS515 and IC82, were confirmed by Northern blot analysis. MS515 was detected in control and nickel oxide (NiO)-transformed MRC-9 cells, as well as in non-small cell lung cancer (NSCLC) EBC-1 cells, while very weak expression was observed in nickel subsulfide (Ni(3)S(2))-transformed MRC-9 cells and small cell lung cancer (SCLC) SBC-2 cells. IC82 could not be detected in control IMR-90 cells, while it was expressed in EBC-1 cells and NiO- and Ni(3)S(2)-transformed IMR-90 cells. These findings indicate that individual nickel compounds have their own target gene(s) in inducing lung cancer. Sequencing analyses showed that the MS515 gene shared a high degree of homology (over 80%) with the gene Mena, which is involved in actin polymerization. IC82 showed 99% homology with human chromosome 4 clone C0440E08 and a coding sequence in the brain. The roles of these two genes in nickel carcinogenesis will be discussed.

Base Sequence↗

PubMed2002

Expressed sequence tags for the chicken genome from a normalized 10-day-old white leghorn whole-embryo cDNA library. 3. DNA sequence analysis of genetic variation in commercial chicken populations.

Single nucleotide polymorphisms (SNPs) have emerged as a major class of DNA markers with the advantage of permitting the development of high-density genetic maps adequate for quantitative trait loci (QTL) identification by linkage-disequilibrium analysis. Here we describe results of a relatively high-depth survey of chicken broiler and layer populations for SNPs in targeted genomic regions of chicken expressed sequence tag (EST) sites. The sequences scanned, representing the composite sequence of 12 amplified fragments for a total of 6489 bp, were randomly distributed, occurring on six different chromosomes or linkage groups in the chicken genome. Although one of the genomic DNA sequences did not match the reference cDNA sequence, another contained an intron that separated two putative exons. The number of SNPs observed within each of the 12 EST-targeted genomic regions ranged from 0 to 10 for a total of 44 and a frequency of 0.7%. About 70% of the polymorphisms were shared between layer and broiler populations. The average heterozygosity within the populations ranged from 0.15 to 0.48, with the layer populations showing the higher heterozygosity. SNPs and oligonucleotides described will provide a resource for genetic analysis in commercial chicken populations. The data appear to indicate that the relative frequency of SNPs in the targeted regions scanned is higher than the frequency reported for any of the other regions scanned to date in other eukaryotic genomes. Additionally, the results suggest that the use of DNA pools may offer an efficient approach to SNP detection in chickens, as has been shown in other vertebrates.

Animals↗

PubMed2006

An expressed sequence tag (EST) library from developing fruits of an Hawaiian endemic mint (Stenogyne rugosa, Lamiaceae): characterization and microsatellite markers.

BACKGROUND: The endemic Hawaiian mints represent a major island radiation that likely originated from hybridization between two North American polyploid lineages. In contrast with the extensive morphological and ecological diversity among taxa, ribosomal DNA sequence variation has been found to be remarkably low. In the past few years, expressed sequence tag (EST) projects on plant species have generated a vast amount of publicly available sequence data that can be mined for simple sequence repeats (SSRs). However, these EST projects have largely focused on crop or otherwise economically important plants, and so far only few studies have been published on the use of intragenic SSRs in natural plant populations. We constructed an EST library from developing fleshy nutlets of Stenogyne rugosa principally to identify genetic markers for the Hawaiian endemic mints. RESULTS: The Stenogyne fruit EST library consisted of 628 unique transcripts derived from 942 high quality ESTs, with 68% of unigenes matching Arabidopsis genes. Relative frequencies of Gene Ontology functional categories were broadly representative of the Arabidopsis proteome. Many unigenes were identified as putative homologs of genes that are active during plant reproductive development. A comparison between unigenes from Stenogyne and tomato (both asterid angiosperms) revealed many homologs that may be relevant for fruit development. Among the 628 unigenes, a total of 44 potentially useful microsatellite loci were predicted. Several of these were successfully tested for cross-transferability to other Hawaiian mint species, and at least five of these demonstrated interesting patterns of polymorphism across a large sample of Hawaiian mints as well as close North American relatives in the genus Stachys. CONCLUSION: Analysis of this relatively small EST library illustrated a broad GO functional representation. Many unigenes could be annotated to involvement in reproductive development. Furthermore, first tests of microsatellite primer pairs have proven promising for the use of Stenogyne rugosa EST SSRs for evolutionary and phylogeographic studies of the Hawaiian endemic mints and their close relatives. Given that allelic repeat length variation in developmental genes of other organisms has been linked with morphological evolution, these SSRs may also prove useful for analyses of phenotypic differences among Hawaiian mints.

5' Untranslated Regions↗

PubMed2004

Single oligonucleotide nested PCR: a rapid method for the isolation of genes and their flanking regions from expressed sequence tags.

We report on the development of a new PCR technique for the isolation of genomic fragments that flank known DNA sequences. This technique, single oligonucleotide nested (SON)-PCR, relies on only two amplification reactions with two or three nested sequence-specific primers. It allows the isolation of DNA regions located on either side of a known DNA sequence, with high specificity. DNA products of 2 kb in size can be generated that all contain one copy of the same primer at both ends. Sequence analysis of these products indicates that the binding of the primers to non-specific DNA sites mainly depends on their overall complementarity to the target sequence. Moreover, analysis shows that short extensions of the primers can occur during the first amplification reaction and that a 2-bp overlap between subsequent primers can target their annealing to their predecessor's sequence. Ninety percent of the DNA products larger than 0.5 kb correspond to fragments of interest and we obtained successful results with various templates and primer sets. SON-PCR therefore seems a very efficient and widely applicable method for the rapid identification of large unknown DNA regions. Based on available expressed sequence tags, this technique was applied to isolate the palH and pacC genes of the phytopathogenic fungus Botrytis cinerea, with their 5' or 3' flanking regions.

Base Sequence↗

PubMed2005

Expressed sequence tag (EST) survey of the highly adapted green algal parasite, Helicosporidium.

Helicosporidia are obligate invertebrate pathogens with a unique and highly adapted mode of infection. The evolutionary history of Helicosporidia has been uncertain, but several recent molecular phylogenetic studies have shown an unexpectedly close relationship to green algae, and specifically to the opportunistic pathogen Prototheca. To date, molecular sequences from Helicosporidia are restricted to those genes used for phylogenetic reconstruction and genes related to the existence and function of its cryptic plastid. We have therefore conducted a small expressed sequence tag (EST) project on Helicosporidium sp., yielding about 700 unique sequences. We have examined the functional distribution of known genes, the distribution of EST abundance, and the prevalence of previously unknown gene sequences. To demonstrate the potential utility of large amounts of data, we have used ribosomal proteins to test whether the phylogenetic position of Helicosporidium inferred from a small number of genes is broadly supported by a large number of genes. We conducted phylogenetic analyses on 69 ribosomal proteins and found that 98% supported the green algal origin of Helicosporidia and 80% support a specific relationship with Prototheca. Overall, these data multiply the available molecular information from Helicosporidium 100-fold, which should provide the basis for new insights into these unusual but interesting parasites.

Chlorophyta↗

PubMed2001

Expressed sequence tags for the chicken genome from a normalized, ten-day-old white leghorn whole embryo cDNA library. 2. Comparative DNA sequence analysis of guinea fowl, quail, and turkey genomes.

Accelerated efforts to develop a high-utility chicken genome map have resulted in the development of resources that may be useful for genetic analysis in other economically important poultry species. Here we describe a total of 26 comparative genomic DNA sequences (CGS) for the guinea fowl, Japanese quail, and domestic turkey developed using 10 primer pairs specific for 10 previously reported, unique, chicken expressed sequence tags (EST). The total length of CGS developed for each of the three species was 4,193, 4,597, and 6,057 bp in quail, turkey, and guinea fowl, respectively. About 70% of the CGS showed significant sequence similarity to reference database sequences, including the reference chicken EST and other avian and nonavian genes. A majority of the between-species comparisons of the CGS from all but two primer pairs were significant and ranged from 81 to 99%. The percentage similarity of the CGS appears to be a function of phylogenetic relatedness and was generally higher for comparisons between the chicken, quail, and turkey and lower between the guinea fowl and chicken, quail, or turkey. Maximum likelihood estimation of the phylogenetic relationships using CGS from two primer pairs also showed a closer relationship, as expected, among chicken, quail, and turkey than between guinea fowl and either chicken, quail, or turkey. Within the guinea fowl, quail, and turkey CGS developed, the total number of single nucleotide polymorphisms detected was 28, 17, and 14, respectively. Together, these resources represent tools that will facilitate genetic analysis of species that have been studied very little and our understanding of their genomes and genome evolution.

Animals↗

PubMed1997

2006 expressed-sequence tags derived from human chromosome 7-enriched cDNA libraries.

The establishment and mapping of gene-specific DNA sequences greatly complement the ongoing efforts to map and sequence all human chromosomes. To facilitate our studies of human chromosome 7, we have generated and analyzed 2006 expressed-sequence tags (ESTs) derived from a collection of direct selection cDNA libraries that are highly enriched for human chromosome 7 gene sequences. Similarity searches indicate that approximately two-thirds of the ESTs are not represented by sequences in the public databases, including those in dbEST. In addition, a large fraction (68%) of the ESTs do not have redundant or overlapping sequences within our collection. Human DNA-specific sequence-tagged sites (STSs) have been developed from 190 of the ESTs. Remarkably, 180 (96%) of these STSs map to chromosome 7, demonstrating the robustness of chromosome enrichment in constructing the direct selection cDNA libraries. Thus far, 140 of these EST-specific STSs have been assigned unequivocally to YAC contigs that are distributed across the chromosome. Together, these studies provide > 2000 ESTs highly enriched for chromosome 7 gene sequences, 180 new chromosome 7 STSs corresponding to ESTs, and a definitive demonstration of the ability to enrich for chromosome-specific cDNAs by direct selection. Furthermore, the libraries, sequence data, and mapping information will contribute to the construction of a chromosome 7 transcript map.

Brain↗

PubMed2004

[Sequencing and analyzing of expressed sequence tags (ESTs) of pig fat tissue].

In this paper,the ESTs of pig fat tissue were sequenced and analyzed using the large-scale DNA sequencing method, 7790 high quality ESTs were gained,from which 4354 genes were obtained using cluster analysis with the STACK-PACK software, including 3609 singlet genes and 745 multicopy genes. The 4354 candidate genes were compared with BLASTN to the nr library (e =1e-10), of which 2712 were known genes, containing 1 987 singlet genes and 725 multicopy genes,there are 2 109 unknown genes and new ESTs. Based on the results of BlastN and the index of GenBank Accenssion No., the known gene expression profile of pig fat were constructed. It showed that the genes participating in metabolism held the highest proportion in the 7 sorts, and in some aspects showed the hearty metabolism activity of fat tissue. 257 total reads of the Major Histocompatibility Complex (MHC) genes in the pig fat tissue were found,including 181 singlet genes and 44 multicopy genes. They account for 44.9% of the cell and organism defense, and 5.4% of all known genes,from this we can see that the MHC has a fairly high expression degree. Comparing all ESTs related with MHC (257reads) with known pig BAC we found the partial sequences (approximately 200 bp) of the ESTs distributing to every exon of. We can predict that the ESTs in MHC contain approximately 200 bp highly consistent regions and every exon possesses one of these regions. Although these MHC sequences in different BAC have different protein domains,they are highly consistent and related with immune functions. When the MHC genes transfer to the next generation,they can duplicate repeatly and inherit stably.

Adipose Tissue↗