郭云濤，苗向陽

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調(diào)控褐色脂肪細胞分化的microRNAs

郭云濤，苗向陽

中國農(nóng)業(yè)科學(xué)院北京畜牧獸醫(yī)研究所，北京 100193

MicroRNA(miRNA)是近年來在真核生物中發(fā)現(xiàn)的一類長約22nt的內(nèi)源性非編碼RNA，在動物中主要通過抑制靶mRNA翻譯，在轉(zhuǎn)錄后水平調(diào)控基因表達。動物體內(nèi)有兩種類型的脂肪組織：褐色和白色脂肪，白色脂肪以甘油三脂形式貯存能量，而褐色脂肪利用甘油三酯產(chǎn)生能量。褐色脂肪因其對肥胖的拮抗作用而對研究肥胖等代謝疾病具有重要意義，大量研究表明miRNA在褐色脂肪細胞分化中扮演著重要角色，其自身也受到多種轉(zhuǎn)錄因子和環(huán)境因子調(diào)控，這個復(fù)雜的調(diào)控網(wǎng)絡(luò)維持了體內(nèi)脂肪組織穩(wěn)態(tài)。文章主要綜述了miRNA在褐色脂肪細胞分化中的最新研究進展，以期為利用miRNA進行肥胖、糖尿病等相關(guān)疾病及其并發(fā)癥的治療提供新思路。

microRNA；褐色脂肪細胞；分化

近年來，隨著人們生活水平的提高，高脂肪食物的過量攝入和久坐的生活習慣，導(dǎo)致超重和肥胖人群的數(shù)目越來越大[1]。肥胖引起了一系列相關(guān)慢性疾病如二型糖尿病、心肌肥大和心腦血管疾病等，已成為威脅人類健康的重大隱患[2, 3]。肥胖最明顯的一個特點就是白色脂肪組織(White adipose tissue, WAT)過度集聚，其細胞水平的表現(xiàn)就是白色脂肪細胞體積增大(肥大)和數(shù)目增加(增生)[4]。哺乳動物體內(nèi)還有另外一種類型的脂肪組織，即褐色脂肪組織(Brown adipose tissue, BAT)，研究人員一度認為BAT僅僅在小型哺乳動物和初生嬰兒中存在，隨著年齡的增長，成人體內(nèi)的BAT維持能量平衡的功能逐漸減少甚至消失，然而，近年來成人體內(nèi)功能性BAT的發(fā)現(xiàn)使其又重新成為研究的熱門。BAT數(shù)目的增加僅僅導(dǎo)致能量消耗的增加而不引起其他組織功能障礙，并且對肥胖有拮抗作用，其功能缺失可能會導(dǎo)致肥胖和胰島素抵抗，遺傳學(xué)抑制或者手術(shù)切除褐色脂肪的小鼠表現(xiàn)出攝食過量和肥胖現(xiàn)象[5~7]。BAT由褐色脂肪細胞、豐富的血管和神經(jīng)組成，最新的研究表明微RNA(microRNA, miRNA)在褐色脂肪細胞分化中起了重要的調(diào)控作用。研究褐色脂肪細胞分化中的miRNA及其作用機制對于解決肥胖等疾病有著至關(guān)重要的意義，本文對褐色脂肪細胞分化中的miRNA研究進行綜述，為利用miRNA進行肥胖等相關(guān)疾病的預(yù)防和治療提供新思路。

1 脂肪細胞的種類和功能

哺乳動物體內(nèi)主要有3種類型的脂肪細胞：白色脂肪細胞、褐色脂肪細胞和米色脂肪細胞，這3種類型脂肪細胞顏色與功能各異，共同維持著體內(nèi)的能量代謝平衡。WAT主要分布在皮下、肌肉、腹部和內(nèi)臟等部位，由白色脂肪細胞組成，能量過剩引起的白色脂肪過度沉積導(dǎo)致了超重和肥胖。白色脂肪細胞中有一個大的脂滴，細胞質(zhì)中線粒體數(shù)量較少，能分泌很多脂肪細胞因子如脂聯(lián)素、瘦素、抵抗素等，可以將體內(nèi)過剩的能量以甘油三酯的形式貯存下來，起著貯存能量和分泌的作用。BAT主要分布在人體的肩胛骨間、頸背部、腋窩、縱隔及腎臟周圍，由褐色脂肪細胞組成，與體質(zhì)量指數(shù)和靜息代謝率有關(guān)[8]。經(jīng)典的褐色脂肪細胞含有很多小的脂滴，細胞質(zhì)中充滿著大量的線粒體，因此看上去是褐色的。線粒體內(nèi)膜上存在特異性高表達的線粒體解偶聯(lián)蛋白1(Mitochondrial brown fat uncoupling protein 1, UCP1)，這是一種褐色脂肪細胞特有的功能蛋白，能消除線粒體內(nèi)膜兩側(cè)的跨膜質(zhì)子濃度梯度，解除線粒體呼吸過程中電子傳遞與氧化磷酸化之間的偶聯(lián)，減緩氧化磷酸化過程，阻礙三磷酸腺苷(ATP)的產(chǎn)生，使能量以熱量的形式釋放出來，從而增加能量的消耗。在寒冷環(huán)境下，褐色脂肪細胞利用甘油三酯產(chǎn)生和消耗熱量[9]，使機體免受寒冷的侵襲。除了白色脂肪細胞和經(jīng)典的褐色脂肪細胞之外，還有一種可以誘導(dǎo)的褐色脂肪細胞(又稱為米色脂肪細胞)，它兼具白色及褐色脂肪細胞的特征，但又不同于兩者，既能儲存能量，又能消耗能量。米色脂肪細胞不像典型的褐色脂肪細胞顯著激活基因表達，而是一種熱源脂肪細胞，在未受刺激情況下其基因表達水平很低，但經(jīng)過環(huán)磷酸腺苷(cAMP)處理之后，其表達量與褐色脂肪細胞相比沒有顯著差異，功能類似經(jīng)典褐色脂肪細胞。

2 microRNA調(diào)控褐色脂肪細胞分化的機制

miRNA是在多種真核細胞和病毒中發(fā)現(xiàn)的一類長約21~22nt的內(nèi)源性非編碼單鏈RNA，通過特異性堿基互補的方式與靶基因信使RNA(mRNA)的3'-UTR結(jié)合，抑制靶mRNA翻譯或誘導(dǎo)其降解，從而在轉(zhuǎn)錄后水平調(diào)控基因的表達[10~12]。miRNA的產(chǎn)生包括以下幾個過程：(1)編碼miRNA的基因在RNA聚合酶Ⅱ的作用下轉(zhuǎn)錄形成初級轉(zhuǎn)錄本pri-miRNA；(2)Pri-miRNA在Drosha/DGCR8復(fù)合體[13]的切割下形成miRNA前體pre-miRNA；(3)Pre- miRNA被Exportin5從細胞核轉(zhuǎn)運到細胞質(zhì)；(4)Pre- miRNA被Dicer酶加工成雙鏈成熟miRNA，隨后雙鏈解旋，形成單鏈成熟miRNA。miRNA的產(chǎn)生過程受到了許多轉(zhuǎn)錄因子調(diào)控，隨后成熟單鏈miRNA形成沉默誘導(dǎo)復(fù)合體RISC，抑制或者降解靶mRNA。自從第一個miRNA-lin-4[14]在線蟲中被發(fā)現(xiàn)以來，越來越多的miRNA被鑒定出來，目前miRbase (http://www.mirbase.org/)收錄的miRNA條目已達28 645條(2014年6月)，并且數(shù)目在逐年增長。miRNA參與了各種生命過程的調(diào)控，包括細胞的增殖、分化和凋亡等，在生物體生長、發(fā)育和疾病發(fā)生等過程中扮演著重要角色[15,16]。

廣義的褐色脂肪細胞來源于(Paired box 7/Myogenic factor5 positive/ negative)前體祖細胞。在信號的刺激下，前體祖細胞首先經(jīng)歷細胞系定型確定褐色向分化，然后經(jīng)歷克隆擴增、生長停滯和終末分化3個步驟形成了褐色脂肪細胞。在這一過程中起決定性作用的是鋅指轉(zhuǎn)錄因子PR結(jié)構(gòu)域包含子16(PR domain containing 16,)，通過與編碼CCAAT-增強子結(jié)合蛋白β(CCAAT/enhancer-binding protein beta, C/EBPβ)的基因形成一個轉(zhuǎn)錄復(fù)合體開關(guān)從而調(diào)控前體向褐色脂肪細胞分化[17, 18]。此外，、過氧化物酶體增殖物激活受體α(Peroxisome proliferator-activated receptor alpha,)、過氧化物酶體增殖物激活受體γ(Peroxisome proliferator-activated receptor gamma,)、激活受體γ共活化劑1α(Peroxisome proliferator-activated receptor gamma coactivator 1-alpha,)和激活受體γ共活化劑1β(Proliferator-activated receptor gamma coactivator 1 beta,)是褐色脂肪標志性基因，在褐色脂肪細胞分化中行使重要功能，其表達量常作為檢測褐色脂肪細胞分化的指標。許多研究表明，miRNA在白色脂肪細胞分化中起到了重要的調(diào)控作用(詳見表1)，其作用的實質(zhì)是對調(diào)節(jié)白色脂肪細胞分化的pRB-E2F、MAPK、SMAD/TGFβ、WNT等信號通路中的一個或多個組件進行靶向調(diào)節(jié)。miRNA對褐色脂肪細胞分化亦起到了重要的調(diào)節(jié)作用，其實質(zhì)是直接靶向作用轉(zhuǎn)錄復(fù)合體或?qū)φ{(diào)控該復(fù)合體表達的上游信號通路的基因進行作用，引起該復(fù)合體的表達量變化，進而影響褐色脂肪細胞分化。

表1 調(diào)控白色脂肪細胞分化的microRNA

注：+代表促進，-代表抑制，H代表人，M代表小鼠，R代表大鼠，P代表豬，空白表示暫不清楚。

3 調(diào)控褐色脂肪細胞分化的microRNA

3.1 miR-133—褐色脂肪細胞分化的負調(diào)控因子

Trajkovski等[50]對寒冷刺激(8℃，24 h)后的C57Bl/6N小鼠和室溫飼養(yǎng)的小鼠褐色脂肪組織進行了miRNA表達譜分析，發(fā)現(xiàn)miR-133在寒冷刺激后發(fā)生了最顯著的下調(diào)，同時與褐色脂肪細胞分化相關(guān)的基因、、和的表達量上調(diào)。生物信息學(xué)分析表明，基因的3'-UTR區(qū)含有與miR-133的2~8種子序列相同的片段，可能是其靶基因，隨后的熒光素酶報告實驗證實了這一點。后續(xù)細胞和個體水平驗證表明，在經(jīng)過腎上腺素刺激或者冷刺激之后，小鼠脂肪組織中家族表達下調(diào)，進而導(dǎo)致miR-133的表達下調(diào)，使其對的抑制作用減弱，促進下游基因、、的表達，進而促進褐色脂肪組織前體祖細胞向成熟褐色和米色脂肪細胞分化。無獨有偶，Yin等[51]利用細胞系追溯實驗和細胞克隆方法證明，褐色脂肪細胞起源于胚胎發(fā)育時期的肌源性先祖細胞。小鼠體內(nèi)成熟的骨骼肌干細胞不僅可以分化成肌細胞，也具有分化成成褐色脂肪細胞的潛能，控制這一過程的決定性因素是一種在骨骼肌干細胞中高表達的肌源性miR-133，它可以直接靶向抑制的表達，增強生肌作用。寒冷刺激或者肌肉再生中miR-133表達被抑制，促進了骨骼肌干細胞向褐色脂肪細胞分化。肌肉再生中抑制miR-133可以促進非偶合呼吸、葡萄糖攝取和產(chǎn)熱作用，增加機體能量消耗提高糖耐量，阻礙飲食性肥胖的發(fā)展。miR-133作為褐色脂肪細胞分化中的負調(diào)控因子為肥胖提供了一個重要的治療靶點。

3.2 miR-155—雙穩(wěn)態(tài)負反饋調(diào)節(jié)回路

Chen等[52]利用深度測序方法比較了褐色脂肪細胞前體和分化后成熟細胞的miRNA表達譜，聚焦到了3個差異表達miRNA：miR-146a、miR-155和miR-223，然后構(gòu)建3個慢病毒載體轉(zhuǎn)染細胞，并利用油紅O染色測定脂質(zhì)積累，發(fā)現(xiàn)只有攜帶miR-155載體轉(zhuǎn)染的細胞發(fā)生了明顯脂質(zhì)減少。miR-155在褐色脂肪組織中富集，在褐色脂肪細胞前體增殖時高表達，但是在誘導(dǎo)分化時表達量下降，它的表達受到抑制脂肪細胞分化信號通路的一個下游作用元件轉(zhuǎn)化生長因子β1(Transforming growth factor beta1,)調(diào)節(jié)。熒光素酶報告實驗表明是miR-155的靶基因，miR-155可以靶向抑制，反過來，也會抑制miR-155表達。構(gòu)建的轉(zhuǎn)基因敲除小鼠(miR-155-/-)中對的抑制被解除，褐色脂肪細胞分化增強，并且促進白色脂肪前體細胞“褐色化”[53]。反之，過表達miR-155的轉(zhuǎn)基因小鼠褐色脂肪組織質(zhì)量下降并出現(xiàn)了褐色脂肪組織功能障礙，其褐色脂肪細胞多呈現(xiàn)未分化前體狀態(tài)。由此可見，miR-155和其直接靶基因形成了一個雙穩(wěn)態(tài)負反饋調(diào)節(jié)回路，巧妙地調(diào)節(jié)了褐色脂肪細胞增殖和分化的 時序。

3.3 miR-193b-365—四元調(diào)控環(huán)

Sun等[54]利用miRNA芯片比較了小鼠附睪白色脂肪、肩胛褐色脂肪和背最長肌的miRNA表達譜，發(fā)現(xiàn)miR-193b-365基因簇在褐色脂肪中特異性表達，該基因簇位于16號染色體長約5 kb的區(qū)域，形成一個雙順反子轉(zhuǎn)錄本。在褐色脂肪前體細胞中，miR-193b 或miR-365 的阻斷可以明顯增強Runt相關(guān)轉(zhuǎn)錄因子1(Runt-related transcription factor 1,)表達，削弱褐色脂肪細胞的脂肪形成，而肌肉生成卻被誘導(dǎo)增強。在C2C12成肌細胞中過表達miR-193b 或miR-365阻遏了肌肉生成的整個過程。熒光素酶報告實驗表明，、細胞粘附相關(guān)/致癌基因調(diào)控蛋白(Cell adhesion molecule-related/down-regulated by oncogenes,)和胰島素樣生長因子結(jié)合蛋白5(Insulin-like growth factor-binding protein 5,)是miR-193b的直接靶基因，是褐色和白色脂肪細胞分化的抑制因子，而和是促生肌因子。miR-193b通過靶向抑制基因，從而減弱了其對前體細胞向褐色脂肪細胞分化過程的抑制作用。miR-193b靶向負調(diào)控和的表達，抑制了前體細胞的成肌分化，從而促進了前體細胞向褐色脂肪細胞分化?？梢酝ㄟ^促進miR-193b的表達，miR-193b靶向抑制，又抑制了和的表達，四者形成了一個以miR-193b為中心的四元環(huán)狀調(diào)節(jié)回路，調(diào)控褐色脂肪細胞分化。Feuermann等[55]在進行小鼠的體內(nèi)實驗時卻得到了相反的結(jié)果，正常小鼠和沉默miR-193b-365-1基因座的轉(zhuǎn)基因小鼠褐色脂肪組織小RNA測序(smallRNA-seq)和轉(zhuǎn)錄組測序(RNA-seq)結(jié)果表明，只有miR-133a發(fā)生顯著下調(diào)，與功能相關(guān)的基因包括和表達水平都沒有發(fā)生顯著改變。隨后進行的β腎上腺素刺激和冷暴露處理的實驗結(jié)果表明處理和對照組之間沒有顯著差異，無論miR-196b存在與否，褐色脂肪組織的功能都沒有受到影響，與功能相關(guān)的miRNA和mRNA表達水平也沒有發(fā)生變化。兩個研究小組得到的結(jié)果相反，這可能是兩個實驗的方法(體外、體內(nèi))以及控制miR-193b-365-1表達的手段不同導(dǎo)致了二者研究結(jié)果的差異。

3.4 miR-196a—褐色化的正調(diào)控者

Mori等[56]發(fā)現(xiàn)：在冷暴露或β腎上腺素刺激后，小鼠白色脂肪組織中miR-196a的表達顯著上調(diào)，而在小鼠白色脂肪中過表達miR-196a誘導(dǎo)了米色脂肪細胞的出現(xiàn)，說明miR-196a對前體祖細胞褐色向分化有促進作用。miR-196a轉(zhuǎn)基因小鼠表現(xiàn)出能量消耗增加和抵抗肥胖的現(xiàn)象，說明誘導(dǎo)出現(xiàn)的米色脂肪細胞具有代謝功能。在前體祖細胞褐色向分化中，miR-196a抑制了其靶基因同源框蛋白Hox-C8[57](Homeobox protein Hox-C8,)的轉(zhuǎn)錄后表達水平，利用染色質(zhì)免疫沉淀(Chromatin Immunoprecipitation, ChIP)法分析小鼠基因組，發(fā)現(xiàn)HOXC8蛋白結(jié)合基因富集，熒光素酶報告實驗發(fā)現(xiàn)HOXC8蛋白的同源突變體缺乏DNA 結(jié)合能力，表明協(xié)同脫乙?；?(Histone deacetylase 3,)作用，調(diào)控3′端序列進而抑制其表達。因此，米色脂肪生成過程中miR-196a 上調(diào)表達抑制基因表達，導(dǎo)致去阻遏，誘導(dǎo)了白色脂肪組織中功能性米色脂肪的發(fā)生。miR-196a作為褐色化的正調(diào)控者，誘導(dǎo)了前體祖細胞褐色向 分化。

3.5 其他影響褐色脂肪細胞分化的microRNA

miR-106b-93簇位于7號染色體上，屬于miR-17家族，已有研究表明該家族的其他成員如miR-17-92[22]促進了白色脂肪細胞的分化。Wu等[59]發(fā)現(xiàn)miR-106b-93也是褐色脂肪細胞分化中的負調(diào)控因子，敲除miR-106b和miR-93顯著誘導(dǎo)了褐色脂肪組織特異性基因如、的表達且加速褐色脂肪細胞中脂滴積聚，過表達miR-106b和miR-93抑制了這些基因的表達，高脂飼料誘導(dǎo)的肥胖小鼠褐色脂肪組織中的miR-106b和miR-93都出現(xiàn)了上調(diào)，這些現(xiàn)象都表明了miR-106b-93對褐色脂肪細胞分化具有抑制作用。Lei等[60]發(fā)現(xiàn)，冷暴露刺激后小鼠的褐色脂肪組織和皮下白色脂肪組織中的miR-27下調(diào)表達，體外褐色脂肪細胞前體分化中也發(fā)現(xiàn)了同樣的下調(diào)。進一步研究表明，miR-27直接靶向調(diào)控了整個褐色脂肪調(diào)控網(wǎng)絡(luò)元件：、、末端水解酶B(Ubiquitin carboxyl-terminal hydrolase B,)和，miR-27通過對的直接作用和對的間接作用，抑制了皮下白色脂肪前體和人工培養(yǎng)細胞的褐色向分化。Karbiener等[61]鑒定出miR-26a和miR-26b是米色脂肪細胞分化中的關(guān)鍵調(diào)控者，過表達miR-26a和miR-26b會加速積聚人多能脂肪源干細胞(Human multipotent adipose-derived stem cells, hMADS)分化過程中脂質(zhì)的積累，抑制miR-26a和miR-26b則會阻止脂質(zhì)積累。miR-26顯著誘導(dǎo)了與能量耗散和線粒體形成相關(guān)的通路，利用靶基因預(yù)測、轉(zhuǎn)錄組學(xué)和RNA干擾方法證明miR-26通過靶向抑制解聚素-金屬蛋白酶結(jié)構(gòu)域包含蛋白17基因(Disintegrin and metalloproteinase domain-containing protein 17,)介導(dǎo)了米色脂肪細胞分化。此外，miR-182[62]、miR-203[62]、miR-378[63]和miR-455[64]也在褐色脂肪細胞分化中起了重要調(diào)控作用，詳見表2。

圖1 miR-133、miR-155、miR-196a和miR-193b-365調(diào)控褐色脂肪細胞分化的分子機制(參考文獻[58]繪制)

表2 調(diào)控褐色脂肪細胞分化的microRNA

注：+代表促進，-代表抑制， H代表人，M代表小鼠，空白表示暫不清楚。

4 展 望

在生物體內(nèi)，一個miRNA可能作用于多個靶基因，也可能是多個miRNA調(diào)控一個靶基因[66]，這種作用構(gòu)成一個調(diào)控網(wǎng)絡(luò)，在某些信號的刺激下，從整體上調(diào)控有機體的生命活動，因此miRNA的作用是通過其復(fù)雜的靶基因協(xié)同調(diào)節(jié)實現(xiàn)的。在脂肪組織中，miRNA通過對轉(zhuǎn)錄復(fù)合體的直接或間接作用調(diào)節(jié)了褐色脂肪細胞分化，同時它自身也受到許多上游轉(zhuǎn)錄因子[67]、脂肪細胞因子[68~76]、調(diào)控蛋白[77, 78]、葡萄糖濃度[79]和飲食[80]的影響，轉(zhuǎn)錄因子、環(huán)境因素、miRNA和下游靶基因及其所在的信號通路形成了一個復(fù)雜的調(diào)控網(wǎng)絡(luò)，調(diào)控了體內(nèi)褐色脂肪細胞分化。針對肥胖以及肥胖相關(guān)并發(fā)癥的治療，不應(yīng)僅局限于miRNA，其上游的轉(zhuǎn)錄因子、下游的靶基因、調(diào)控蛋白和環(huán)境理化因素也具有成為治療靶標的潛能。對褐色脂肪細胞分化乃至肥胖等的研究應(yīng)該在這個動態(tài)的網(wǎng)絡(luò)中尋找答案，二代測序技術(shù)和生物芯片技術(shù)為人們提供了一個強有力的工具。目前，二代測序技術(shù)的成本在逐年降低，利用二代測序技術(shù)對miRNA進行研究已經(jīng)成為一個重要的方法，與傳統(tǒng)的芯片技術(shù)相比，二代測序技術(shù)有許多優(yōu)勢，如新miRNA的發(fā)現(xiàn)、開放性等都是芯片技術(shù)無法比擬的，芯片技術(shù)亦有其優(yōu)勢，如成本低廉和表達量測定準確等，在進行miRNA研究時可以根據(jù)研究目的靈活選擇。對褐色脂肪細胞分化中miRNA的功能研究，也可借鑒Calura等[81]在通路中研究miRNA作用機制的方法，結(jié)合上游轉(zhuǎn)錄因子、細胞因子、表型相關(guān)的靶基因所在通路，甚至代謝組、蛋白質(zhì)組等，繪制miRNA參與的調(diào)控網(wǎng)絡(luò)，在網(wǎng)絡(luò)中發(fā)現(xiàn)關(guān)鍵的基因或代謝途徑。目前，已經(jīng)開發(fā)出了一些治療肥胖的藥物和治療方案，但肥胖問題的解決依然任重道遠[82]。隨著調(diào)控脂肪細胞分化研究的深入，人們對這個復(fù)雜的調(diào)控網(wǎng)絡(luò)的了解越來越透徹，相信在不久的將來一定能夠研究出更加有效的治療肥胖的藥物或方法。

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(責任編委: 陳雁)

MicroRNAs in the regulation of brown adipocyte differentiation

Yuntao Guo, Xiangyang Miao

MicroRNAs (miRNAs), a class of endogenous non-coding RNA about 22 nucleotide long, regulate gene expression at the post-transcription level by inhibiting the translation or inducing the degradation of their target mRNAs in organisms. There are two types of adipose tissues: brown and white. White adipose tissues store energy in the form of triglycerides (TGs), while brown adipose tissues catabolize TGs to generate energy. Brown adipose tissues are of great importance to the research of obesity and related metabolic diseases due to their function of preventing people from obesity. A lot of studies have revealed that miRNAs play crucial roles in regulating brown adipocyte differentiation and are modulated by lots of transcription factors and environmental factors, which form a complex regulatory network maintaining the homeostasis of adipose tissues. In this review, we summarize the latest studies of miRNAs in brown adipocyte differentiation, which might provide new strategies for the treatment of obesity and other related diseases.

microRNA; brown adipocyte; differentiation

2014-10-19;

2014-12-16

轉(zhuǎn)基因生物新品種培育科技重大專項(編號：2009ZX08008-004B, 2008ZX08008-003)，國家高技術(shù)研究發(fā)展計劃(863計劃)項目(編號：2008AA10Z140)，國家自然科學(xué)基金項目(編號：30571339)，中國農(nóng)業(yè)科學(xué)院創(chuàng)新基金項目(編號：2004-院-1)，中央級公益性科研院所基本科研業(yè)務(wù)費專項資金項目(編號：2013ywf-yb-5, 2013ywf-zd-2)和中國農(nóng)業(yè)科學(xué)院農(nóng)業(yè)科技創(chuàng)新項目(編號：ASTIP-IAS05)資助

郭云濤，碩士，專業(yè)方向：轉(zhuǎn)基因與細胞工程。E-mail: yuntao008@126.com

苗向陽，研究員，博士，博士生導(dǎo)師，研究方向：基因工程與功能基因組學(xué)及轉(zhuǎn)基因動物。E-mail: mxy32@sohu.com

10.16288/j.yczz.14-360

2015-1-7 8:50:40

http://www.cnki.net/kcms/detail/11.1913.R.20150107.0850.002.html