Anophthalmia is defined as a complete absence of one eye or both the eyes,while microphthalmia represents the presence of a small eye within the orbit.The estimated birth prevalence for anophthalmia is approximately 3...Anophthalmia is defined as a complete absence of one eye or both the eyes,while microphthalmia represents the presence of a small eye within the orbit.The estimated birth prevalence for anophthalmia is approximately 3 per 100000 live births,and for microphthalmia,it is around 14 per 100000 live births.However,combined evidence suggests that the prevalence of these malformations could be as high as 30 per 100000 individuals.Microphthalmia is reported to occur in 3.2%to 11.2%of blind children.Anophthalmia and microphthalmia(A/M)are part of a phenotypic spectrum alongside ocular coloboma,hypothesized to share a com-mon genetic basis.Both A/M can occur in isolation or as part of a syndrome.Their complex etiology involves chromosomal aberrations,monogenic inheritance pattern,and the contribution of environmental factors such as gestational-acquired infections,maternal vitamin A deficiency(VAD),exposure to X-rays,solvent misuse,and thalidomide exposure.A/M exhibit significant clinical and genetic heterogeneity with over 90 genes identified so far.Familial cases of A/M have a complex genetic basis,including all Mendelian modes of inheritance,i.e.,autosomal dominant,recessive,and X-linked.Most cases arise sporadically due to de novo mutations.Examining gene expression during eye development and the effects of various environmental variables will help us better understand the phenotypic heterogeneity found in A/M,leading to more effective diagnosis and management strategies.The present review focuses on key genetic factors,developmental abnormalities,and environmental modifiers linked with A/M.It also emphasizes at potential research areas including multiomic methods and disease modeling with induced pluripotent stem cell technologies,which aim to create innovative treatment options.展开更多
The microphthalmia(MiT)subfamily of transcription factors includes TFE3,TFEB,TFEC,and MITF.In the 2016 World Health Organization classification,MiT family translocation renal cell carcinoma(tRCC)including Xp11 tRCC an...The microphthalmia(MiT)subfamily of transcription factors includes TFE3,TFEB,TFEC,and MITF.In the 2016 World Health Organization classification,MiT family translocation renal cell carcinoma(tRCC)including Xp11 tRCC and t(6;11)RCC,was newly defined as an RCC subtype.Xp11 and t(6;11)RCC are characterized by the rearrangement of the MiT transcription factors TFE3 and TFEB,respectively.Recent studies identified the fusion partner-dependent clinicopathological and immunohistochemical features in TFE3-rearranged RCC.Furthermore,RCC with TFEB amplification,melanotic MiT family translocation neoplasms,was identified may as a unique subtype of MiT family associated renal neoplasms,along with MITF associated RCC.In this review,we will collect available literature of these newly-described RCCs,analyze their clinicopathological and immunohistochemical features,and summarize their molecular and genetic evidences.We expect this review would be beneficial for the understanding of these rare subtypes of RCCs,and eventually promote clinical management strategies.展开更多
AIM:To evaluate volume differences between anterior and posterior orbit and demographic characteristics of Chinese patients with congenital microphthalmia.METHODS:A retrospective cohort study,involving 169 unilateral ...AIM:To evaluate volume differences between anterior and posterior orbit and demographic characteristics of Chinese patients with congenital microphthalmia.METHODS:A retrospective cohort study,involving 169 unilateral congenital microphthalmia patients aged between 1 and 57 years old was conducted.Three-dimensional images of the orbit were generated from past CT scans,and digital orbital volume comprehensive measurement was done.The measured data included orbital volume(OBV),posterior orbital volume(POV),orbital width(OBW),orbital height(OBH),orbital depth(OBD),and posterior orbital area ratio.RESULTS:Significant differences were observed among OBV,POV,OBW,OBH,and OBD of the affected and unaffected eyes in different age-based groups(all P<0.001).Among them,OBH had the greatest different.The mean microphthalmic to contralateral ratio(MCR) of OBV,POV,OBW,and OBH continuously increased from 1 to 3 years old,whereas the MCR of POV decreased from 3 to 17 years old.The MCR of OBD was not found to be correlated to age.There was no significant difference between OBV,POV,OBW,and OBH in ages from 13 years old to adulthood(all P>0.05).The difference in posterior orbital area ratio between the affected and unaffected groups was not statistically significant(P>0.05).CONCLUSION:OBH is maximally affected,whereas OBD is minimally affected by microphthalmia.Posterior orbital retardation began 2y prior to orbital retardation and occurred at 3 years old in the affected eye,suggesting that intervention therapy should be done before the age of 4.展开更多
The present study investigates the expression of microphthalmia-associated transcription factor(MITF) and its contribution to the melanin deposition in Liancheng white ducks.Nested PCR was used to clone the MITF gene ...The present study investigates the expression of microphthalmia-associated transcription factor(MITF) and its contribution to the melanin deposition in Liancheng white ducks.Nested PCR was used to clone the MITF gene sequence from the skin tissue of female Liancheng white ducks.Ultraviolet spectrophotometry was used to detect the melanin deposition.MITF mRNA expression and melanin deposition in different tissues and organs were detected and their correlation was analyzed.The MITF gene(GenBank number: MG516570) was 1 323 bp in length,contains a complete CDS region(34-1 323 bp) and codes 429 amino acids with 100% homology to the MITF of Anas platyrhynchos and over 95% homology to those of Gallus gallus and Coturnix japonica.Genetic evolution analysis reveals a close relationship of Liancheng white ducks with A.platyrhynchos,and also to lesser extents with Anser cygnoides,silky fowl and G.gallus,as well as Sus scrofa,Ovis aries and other mammals.Real-time quantitative PCR(qPCR) analysis demonstrated that MITF was expressed in skin,gizzard,liver,kidney and muscle,and of these tissues,its expression was the highest in the skin tissue(skin>gizzard>liver>kidney>muscle).Ultraviolet spectrophotometry showed that melanin deposition was positively correlated with the MITF expression level in these five tissues and organs(P<0.05).Together,these results demonstrated a tissue-specific pattern of MITF expression and a positive correlation between MITF expression and melanin deposition,indicating that MITF expression may contribute to the melanin deposition in Liancheng white ducks.展开更多
AIM:To identify the genetic factors underlying anophthalmia and microphthalmia(A/M),and to perform computational analysis to verify the pathophysiological mechanisms of the disease.METHODS:This study investigated a co...AIM:To identify the genetic factors underlying anophthalmia and microphthalmia(A/M),and to perform computational analysis to verify the pathophysiological mechanisms of the disease.METHODS:This study investigated a consanguineous Pakistani family with multiple affected individuals.Clinical evaluations were conducted using A-Scan and ophthalmic B-Scan ultrasonography(B-Scan).To identify the diseasecausing variant,whole exome sequencing(WES)and Sanger sequencing were performed.In silico functional analyses were carried out using AlphaFold(for protein modeling)and ClusPro(for protein docking analysis)tools,and the hydrodynamic properties of the protein were determined via molecular dynamics simulations.RESULTS:Clinical analysis of the five patients revealed severe phenotypes of bilateral anophthalmia.Ocular B-Scan did not detect ocular tissue or intraocular fluid,thus confirming the diagnosis of anophthalmia in all patients.Due to these structural defects,all patients exhibited complete blindness and absence of light perception;additionally,two patients had mild to moderate intellectual disability.Genetic analysis identified a splice site variant[NM_000693.2:c.884-2_885dup;p.(Asp296SerfsTer35)]in the 9^(th)exon of the ALDH1A3 gene.CONCLUSION:The present study expands the genetic spectrum of ALDH1A3 and contributes to establishing the genotype-phenotype correlation for this gene.展开更多
Congenital microphthalmia is a developmental ocular disorder and might be caused by the mutations in the genes involved in eye development. To uncover the genetic cause in a six-generation Chinese pedigree with autoso...Congenital microphthalmia is a developmental ocular disorder and might be caused by the mutations in the genes involved in eye development. To uncover the genetic cause in a six-generation Chinese pedigree with autosomal dominant congenital microphthalmia, we performed genescan and linkage analysis in this family. Fourteen microsatellite markers on chromosomes 3, 11, 14 and 15 were selected as genetic markers according to the five pre-viously reported loci associated with microphthalmia (MITF, SOX2, PAX6, MCOP and NNO2). The genomic DNA of each member in the pedigree was amplified with 14 pairs of fluorescence labeled primers. Genome screening and genotyping were conducted on ABI377 DNA sequencer and linkage analysis was performed with Linkage software package. All two-point LOD scores of linkage analysis between the suggested disease genes and microsatellite markers were <-2, which indicated that none of the five genes were responsible for microphthalmia in this Chinese family. Microphthalmia in this family may be caused by mutation in a new gene which is essential in eye development.展开更多
目的:总结MAB21L2基因的变异和临床特点,并与高度同源的MAB21L1基因进行比较。方法:对中山眼科中心临床基因数据库中MAB21L2基因变异患者进行基因型和表型分析,回顾性分析既往文献报道的MAB21L2基因和高度同源基因MAB21L1变异的表型-基...目的:总结MAB21L2基因的变异和临床特点,并与高度同源的MAB21L1基因进行比较。方法:对中山眼科中心临床基因数据库中MAB21L2基因变异患者进行基因型和表型分析,回顾性分析既往文献报道的MAB21L2基因和高度同源基因MAB21L1变异的表型-基因型的关系。结果:在2个小眼畸形家系中发现2个MAB21L2基因杂合变异:先证者1携带已知变异c.151C>G/p.(Arg51Gly),患者双眼小眼畸形伴虹膜脉络膜缺损,伴骨关节屈曲。母亲携带相同杂合变异但表型正常;先证者2携带未报道的变异c.1042G>T/p.(Glu348*),左眼小眼畸形,右眼正常且无全身异常。结合文献回顾发现,在显性遗传模式下,80%的MAB21L2杂合致病变异(20/25)和100%的MAB21L1杂合致病变异(25/25)发生在氨基酸49-52区域,导致小眼无眼或眼缺损异常(microphthalmia,anophthalmia or coloboma,MAC);携带该区域MAB21L2基因杂合突变的患者除MAC外,部分还伴骨骼关节发育异常(12/24,50%);杂合截短变异发生在MAB21L2基因可导致MAC(5/5,100%),而发生在MAB21L1则不致病。结论:在2个小眼畸形家系中发现了MAB21L2基因1个新致病变异和1个已知热点致病变异,通过文献综述比较和总结了MAB21L1和MAB21L2基因的突变频谱以及基因型-表型相互关系,为此类基因缺陷导致遗传病的诊断和鉴别诊断提供依据。展开更多
旨在研究10-羟基喜树碱(10-hydroxycamptothecin,HCPT)和白藜芦醇(Resveratrol,Res)对体外培养的小鼠恶性黑色素瘤B16F10细胞的增殖及黑色素合成抑制机理。利用MTT法、显微观察、L-Dopa氧化法、Na OH裂解法分析不同浓度HCPT和Res对细胞...旨在研究10-羟基喜树碱(10-hydroxycamptothecin,HCPT)和白藜芦醇(Resveratrol,Res)对体外培养的小鼠恶性黑色素瘤B16F10细胞的增殖及黑色素合成抑制机理。利用MTT法、显微观察、L-Dopa氧化法、Na OH裂解法分析不同浓度HCPT和Res对细胞增殖、细胞形态、酪氨酸酶活性及黑色素合成含量的影响。荧光半定量PCR方法(Semi-RT-PCR)分析该化合物对黑色素合成关键因子酪氨酸酶(TYR)和小眼相关转录因子(MITF)基因表达的影响。结果表明HCPT(40、80、120、160和200μmol/L)和Res(80、120、160和200μmol/L)能够通过诱导细胞凋亡抑制B16F10细胞的增殖,同时对酪氨酸酶活性和细胞黑色素生成具有明显抑制作用(P<0.05),且呈现浓度依赖性。另外,不同浓度的HCPT以及高浓度Res(120和160μmol/L)能够显著下调B16F10细胞TYR和MITF基因的mRNA水平。HCPT和Res可能通过诱导细胞凋亡抑制B16F10细胞的增殖,同时通过下调MITF基因转录,抑制TYR m RNA的表达及TYR酶活性,进而抑制细胞黑色素的生成。展开更多
黑色素合成是极其复杂的过程,其中涉及多种基因和miRNAs的参与。miR-186-5p在绵羊不同毛色皮肤中差异表达,说明其可能与毛色形成有关,生物信息学预测和绵羊不同毛色皮肤中miR-186-5p和Mitf的差异表达间接说明二者可能存在靶向关系,双荧...黑色素合成是极其复杂的过程,其中涉及多种基因和miRNAs的参与。miR-186-5p在绵羊不同毛色皮肤中差异表达,说明其可能与毛色形成有关,生物信息学预测和绵羊不同毛色皮肤中miR-186-5p和Mitf的差异表达间接说明二者可能存在靶向关系,双荧光报告直接证实了二者的靶向关系。为了证实miR-186-5p在黑色素形成中的作用,本研究构建miR-186-5p真核表达载体,并转染绵羊黑素细胞。结果显示,miR-186-5p通过与Mitf mRNAs的3′UTR结合抑制Mitf的表达和翻译。MITF是Tyr基因家族的调节因子。实时荧光聚合酶链反应(quantitative real time polymerase chain reaction, qRT-PCR)和Western免疫印迹结果表明,过表达miR-186-5p引起的MITF下调抑制了TYR、TYRP1和TYRP2的表达。其中,mRNA表达水平分别下降34%、66%和52%;蛋白质表达水平分别下降32%、6%和46%。分光光度检测结果显示,黑色素含量下降59%倍。上述结果表明,miR-186-5p通过抑制靶基因Mitf的表达,抑制了绵羊黑素细胞内黑色素的生成。展开更多
文摘Anophthalmia is defined as a complete absence of one eye or both the eyes,while microphthalmia represents the presence of a small eye within the orbit.The estimated birth prevalence for anophthalmia is approximately 3 per 100000 live births,and for microphthalmia,it is around 14 per 100000 live births.However,combined evidence suggests that the prevalence of these malformations could be as high as 30 per 100000 individuals.Microphthalmia is reported to occur in 3.2%to 11.2%of blind children.Anophthalmia and microphthalmia(A/M)are part of a phenotypic spectrum alongside ocular coloboma,hypothesized to share a com-mon genetic basis.Both A/M can occur in isolation or as part of a syndrome.Their complex etiology involves chromosomal aberrations,monogenic inheritance pattern,and the contribution of environmental factors such as gestational-acquired infections,maternal vitamin A deficiency(VAD),exposure to X-rays,solvent misuse,and thalidomide exposure.A/M exhibit significant clinical and genetic heterogeneity with over 90 genes identified so far.Familial cases of A/M have a complex genetic basis,including all Mendelian modes of inheritance,i.e.,autosomal dominant,recessive,and X-linked.Most cases arise sporadically due to de novo mutations.Examining gene expression during eye development and the effects of various environmental variables will help us better understand the phenotypic heterogeneity found in A/M,leading to more effective diagnosis and management strategies.The present review focuses on key genetic factors,developmental abnormalities,and environmental modifiers linked with A/M.It also emphasizes at potential research areas including multiomic methods and disease modeling with induced pluripotent stem cell technologies,which aim to create innovative treatment options.
文摘The microphthalmia(MiT)subfamily of transcription factors includes TFE3,TFEB,TFEC,and MITF.In the 2016 World Health Organization classification,MiT family translocation renal cell carcinoma(tRCC)including Xp11 tRCC and t(6;11)RCC,was newly defined as an RCC subtype.Xp11 and t(6;11)RCC are characterized by the rearrangement of the MiT transcription factors TFE3 and TFEB,respectively.Recent studies identified the fusion partner-dependent clinicopathological and immunohistochemical features in TFE3-rearranged RCC.Furthermore,RCC with TFEB amplification,melanotic MiT family translocation neoplasms,was identified may as a unique subtype of MiT family associated renal neoplasms,along with MITF associated RCC.In this review,we will collect available literature of these newly-described RCCs,analyze their clinicopathological and immunohistochemical features,and summarize their molecular and genetic evidences.We expect this review would be beneficial for the understanding of these rare subtypes of RCCs,and eventually promote clinical management strategies.
文摘AIM:To evaluate volume differences between anterior and posterior orbit and demographic characteristics of Chinese patients with congenital microphthalmia.METHODS:A retrospective cohort study,involving 169 unilateral congenital microphthalmia patients aged between 1 and 57 years old was conducted.Three-dimensional images of the orbit were generated from past CT scans,and digital orbital volume comprehensive measurement was done.The measured data included orbital volume(OBV),posterior orbital volume(POV),orbital width(OBW),orbital height(OBH),orbital depth(OBD),and posterior orbital area ratio.RESULTS:Significant differences were observed among OBV,POV,OBW,OBH,and OBD of the affected and unaffected eyes in different age-based groups(all P<0.001).Among them,OBH had the greatest different.The mean microphthalmic to contralateral ratio(MCR) of OBV,POV,OBW,and OBH continuously increased from 1 to 3 years old,whereas the MCR of POV decreased from 3 to 17 years old.The MCR of OBD was not found to be correlated to age.There was no significant difference between OBV,POV,OBW,and OBH in ages from 13 years old to adulthood(all P>0.05).The difference in posterior orbital area ratio between the affected and unaffected groups was not statistically significant(P>0.05).CONCLUSION:OBH is maximally affected,whereas OBD is minimally affected by microphthalmia.Posterior orbital retardation began 2y prior to orbital retardation and occurred at 3 years old in the affected eye,suggesting that intervention therapy should be done before the age of 4.
基金supported by the National Natural Science Foundation of China (31372474)the National Guidance Project for Local Science and Technology Development,China (2018L3004)+3 种基金the National and FNU Training Program of Innovation and Enterpreneurship for Undergraduates, China (201910394023, CXXL2019268 and CXXL2019274)the Fujian Province Public Welfare Scientific Project, China (018R1023-2)the Fujian Development and Reform Commission “Five News” Project of China (fjfgw201806)the Young Talent Innovation Funding of Fujian Academy of Agricultural Sciences of China (YC2017-7 and MYQJ2015-5)
文摘The present study investigates the expression of microphthalmia-associated transcription factor(MITF) and its contribution to the melanin deposition in Liancheng white ducks.Nested PCR was used to clone the MITF gene sequence from the skin tissue of female Liancheng white ducks.Ultraviolet spectrophotometry was used to detect the melanin deposition.MITF mRNA expression and melanin deposition in different tissues and organs were detected and their correlation was analyzed.The MITF gene(GenBank number: MG516570) was 1 323 bp in length,contains a complete CDS region(34-1 323 bp) and codes 429 amino acids with 100% homology to the MITF of Anas platyrhynchos and over 95% homology to those of Gallus gallus and Coturnix japonica.Genetic evolution analysis reveals a close relationship of Liancheng white ducks with A.platyrhynchos,and also to lesser extents with Anser cygnoides,silky fowl and G.gallus,as well as Sus scrofa,Ovis aries and other mammals.Real-time quantitative PCR(qPCR) analysis demonstrated that MITF was expressed in skin,gizzard,liver,kidney and muscle,and of these tissues,its expression was the highest in the skin tissue(skin>gizzard>liver>kidney>muscle).Ultraviolet spectrophotometry showed that melanin deposition was positively correlated with the MITF expression level in these five tissues and organs(P<0.05).Together,these results demonstrated a tissue-specific pattern of MITF expression and a positive correlation between MITF expression and melanin deposition,indicating that MITF expression may contribute to the melanin deposition in Liancheng white ducks.
基金Supported by Taif University,Taif,Saudi Arabia(TU-DSPP-2024-05).
文摘AIM:To identify the genetic factors underlying anophthalmia and microphthalmia(A/M),and to perform computational analysis to verify the pathophysiological mechanisms of the disease.METHODS:This study investigated a consanguineous Pakistani family with multiple affected individuals.Clinical evaluations were conducted using A-Scan and ophthalmic B-Scan ultrasonography(B-Scan).To identify the diseasecausing variant,whole exome sequencing(WES)and Sanger sequencing were performed.In silico functional analyses were carried out using AlphaFold(for protein modeling)and ClusPro(for protein docking analysis)tools,and the hydrodynamic properties of the protein were determined via molecular dynamics simulations.RESULTS:Clinical analysis of the five patients revealed severe phenotypes of bilateral anophthalmia.Ocular B-Scan did not detect ocular tissue or intraocular fluid,thus confirming the diagnosis of anophthalmia in all patients.Due to these structural defects,all patients exhibited complete blindness and absence of light perception;additionally,two patients had mild to moderate intellectual disability.Genetic analysis identified a splice site variant[NM_000693.2:c.884-2_885dup;p.(Asp296SerfsTer35)]in the 9^(th)exon of the ALDH1A3 gene.CONCLUSION:The present study expands the genetic spectrum of ALDH1A3 and contributes to establishing the genotype-phenotype correlation for this gene.
基金This work was supported by Science and Technology Committee of Yunnan Provincethe National Natural Science Foundation of China(Grant No.30021004).
文摘Congenital microphthalmia is a developmental ocular disorder and might be caused by the mutations in the genes involved in eye development. To uncover the genetic cause in a six-generation Chinese pedigree with autosomal dominant congenital microphthalmia, we performed genescan and linkage analysis in this family. Fourteen microsatellite markers on chromosomes 3, 11, 14 and 15 were selected as genetic markers according to the five pre-viously reported loci associated with microphthalmia (MITF, SOX2, PAX6, MCOP and NNO2). The genomic DNA of each member in the pedigree was amplified with 14 pairs of fluorescence labeled primers. Genome screening and genotyping were conducted on ABI377 DNA sequencer and linkage analysis was performed with Linkage software package. All two-point LOD scores of linkage analysis between the suggested disease genes and microsatellite markers were <-2, which indicated that none of the five genes were responsible for microphthalmia in this Chinese family. Microphthalmia in this family may be caused by mutation in a new gene which is essential in eye development.
文摘目的:总结MAB21L2基因的变异和临床特点,并与高度同源的MAB21L1基因进行比较。方法:对中山眼科中心临床基因数据库中MAB21L2基因变异患者进行基因型和表型分析,回顾性分析既往文献报道的MAB21L2基因和高度同源基因MAB21L1变异的表型-基因型的关系。结果:在2个小眼畸形家系中发现2个MAB21L2基因杂合变异:先证者1携带已知变异c.151C>G/p.(Arg51Gly),患者双眼小眼畸形伴虹膜脉络膜缺损,伴骨关节屈曲。母亲携带相同杂合变异但表型正常;先证者2携带未报道的变异c.1042G>T/p.(Glu348*),左眼小眼畸形,右眼正常且无全身异常。结合文献回顾发现,在显性遗传模式下,80%的MAB21L2杂合致病变异(20/25)和100%的MAB21L1杂合致病变异(25/25)发生在氨基酸49-52区域,导致小眼无眼或眼缺损异常(microphthalmia,anophthalmia or coloboma,MAC);携带该区域MAB21L2基因杂合突变的患者除MAC外,部分还伴骨骼关节发育异常(12/24,50%);杂合截短变异发生在MAB21L2基因可导致MAC(5/5,100%),而发生在MAB21L1则不致病。结论:在2个小眼畸形家系中发现了MAB21L2基因1个新致病变异和1个已知热点致病变异,通过文献综述比较和总结了MAB21L1和MAB21L2基因的突变频谱以及基因型-表型相互关系,为此类基因缺陷导致遗传病的诊断和鉴别诊断提供依据。
文摘旨在研究10-羟基喜树碱(10-hydroxycamptothecin,HCPT)和白藜芦醇(Resveratrol,Res)对体外培养的小鼠恶性黑色素瘤B16F10细胞的增殖及黑色素合成抑制机理。利用MTT法、显微观察、L-Dopa氧化法、Na OH裂解法分析不同浓度HCPT和Res对细胞增殖、细胞形态、酪氨酸酶活性及黑色素合成含量的影响。荧光半定量PCR方法(Semi-RT-PCR)分析该化合物对黑色素合成关键因子酪氨酸酶(TYR)和小眼相关转录因子(MITF)基因表达的影响。结果表明HCPT(40、80、120、160和200μmol/L)和Res(80、120、160和200μmol/L)能够通过诱导细胞凋亡抑制B16F10细胞的增殖,同时对酪氨酸酶活性和细胞黑色素生成具有明显抑制作用(P<0.05),且呈现浓度依赖性。另外,不同浓度的HCPT以及高浓度Res(120和160μmol/L)能够显著下调B16F10细胞TYR和MITF基因的mRNA水平。HCPT和Res可能通过诱导细胞凋亡抑制B16F10细胞的增殖,同时通过下调MITF基因转录,抑制TYR m RNA的表达及TYR酶活性,进而抑制细胞黑色素的生成。
文摘黑色素合成是极其复杂的过程,其中涉及多种基因和miRNAs的参与。miR-186-5p在绵羊不同毛色皮肤中差异表达,说明其可能与毛色形成有关,生物信息学预测和绵羊不同毛色皮肤中miR-186-5p和Mitf的差异表达间接说明二者可能存在靶向关系,双荧光报告直接证实了二者的靶向关系。为了证实miR-186-5p在黑色素形成中的作用,本研究构建miR-186-5p真核表达载体,并转染绵羊黑素细胞。结果显示,miR-186-5p通过与Mitf mRNAs的3′UTR结合抑制Mitf的表达和翻译。MITF是Tyr基因家族的调节因子。实时荧光聚合酶链反应(quantitative real time polymerase chain reaction, qRT-PCR)和Western免疫印迹结果表明,过表达miR-186-5p引起的MITF下调抑制了TYR、TYRP1和TYRP2的表达。其中,mRNA表达水平分别下降34%、66%和52%;蛋白质表达水平分别下降32%、6%和46%。分光光度检测结果显示,黑色素含量下降59%倍。上述结果表明,miR-186-5p通过抑制靶基因Mitf的表达,抑制了绵羊黑素细胞内黑色素的生成。
