中华实验眼科杂志
中華實驗眼科雜誌
중화실험안과잡지
CHINESE JOURNAL OF EXPERIMENTAL OPHTHALMOLOGY
2012年
5期
397-402
,共6页
刘瑛%顾欣祖%LU Michael%DING Chuan-qing
劉瑛%顧訢祖%LU Michael%DING Chuan-qing
류영%고흔조%LU Michael%DING Chuan-qing
Smad4%泪腺%发育%转基因小鼠
Smad4%淚腺%髮育%轉基因小鼠
Smad4%루선%발육%전기인소서
Smad4%Lacrimal gland%Development%Transgenic mice
背景Smad4是转化牛长因子β(TGF-β)超家族分子信号通路的一个关键调节因子.在许多组织器官的正常发育中起重要作用,目前其在泪腺发育中的作用鲜有报道. 目的 利用Smad4条件性基因敲除小鼠模型探讨Smad4在泪腺失活后对其发育的影响.方法 通过使用Pax6启动子控制下的Le-Cre转基因小鼠和Smad4条件基因敲除小鼠建立晶状体外胚层特异性Smad4条件性基因敲除小鼠(C57BL/6小鼠系),失活Smad4在泪腺、晶状体、角膜和眼睑外胚层的表达,采用常规组织学方法观察其泪腺的形态学改变,同时Cre及Rosa26报道基因双转基因小鼠通过LacZ染色观察泪腺发育过程中与同龄野生型小鼠泪腺发育和形态的差别.每组至少使用6只同龄小鼠或小鼠胚胎进行比较.结果 LacZ染色显示,与孕15.0d的野生型相比,同胎龄Smad4基因敲除小鼠胚胎仍可形成泪腺原芽,但其明显短小；孕16.5d的野生型泪腺芽已有分支,而变异型仍未见分支,仅前端变圆钝,至孕18.0d虽有分支并出现腺泡,但其分支、腺泡大小和数目均明显少于野生型；组织解剖学发现Smad4变异小鼠出生后其泪腺发育仍旧缓慢,表现为其腺体大小、分叶及腺泡数目均较同龄野生小鼠者显著减少,并自P7起出现渐进性增加的色素及脂肪堆积,至成熟期,腺体完全被脂肪组织和色索所取代.结论 Smad4对于小鼠泪腺的正常发育有着重要的作用,并可能影响腺体内色素和脂肪的代谢.
揹景Smad4是轉化牛長因子β(TGF-β)超傢族分子信號通路的一箇關鍵調節因子.在許多組織器官的正常髮育中起重要作用,目前其在淚腺髮育中的作用鮮有報道. 目的 利用Smad4條件性基因敲除小鼠模型探討Smad4在淚腺失活後對其髮育的影響.方法 通過使用Pax6啟動子控製下的Le-Cre轉基因小鼠和Smad4條件基因敲除小鼠建立晶狀體外胚層特異性Smad4條件性基因敲除小鼠(C57BL/6小鼠繫),失活Smad4在淚腺、晶狀體、角膜和眼瞼外胚層的錶達,採用常規組織學方法觀察其淚腺的形態學改變,同時Cre及Rosa26報道基因雙轉基因小鼠通過LacZ染色觀察淚腺髮育過程中與同齡野生型小鼠淚腺髮育和形態的差彆.每組至少使用6隻同齡小鼠或小鼠胚胎進行比較.結果 LacZ染色顯示,與孕15.0d的野生型相比,同胎齡Smad4基因敲除小鼠胚胎仍可形成淚腺原芽,但其明顯短小；孕16.5d的野生型淚腺芽已有分支,而變異型仍未見分支,僅前耑變圓鈍,至孕18.0d雖有分支併齣現腺泡,但其分支、腺泡大小和數目均明顯少于野生型；組織解剖學髮現Smad4變異小鼠齣生後其淚腺髮育仍舊緩慢,錶現為其腺體大小、分葉及腺泡數目均較同齡野生小鼠者顯著減少,併自P7起齣現漸進性增加的色素及脂肪堆積,至成熟期,腺體完全被脂肪組織和色索所取代.結論 Smad4對于小鼠淚腺的正常髮育有著重要的作用,併可能影響腺體內色素和脂肪的代謝.
배경Smad4시전화우장인자β(TGF-β)초가족분자신호통로적일개관건조절인자.재허다조직기관적정상발육중기중요작용,목전기재루선발육중적작용선유보도. 목적 이용Smad4조건성기인고제소서모형탐토Smad4재루선실활후대기발육적영향.방법 통과사용Pax6계동자공제하적Le-Cre전기인소서화Smad4조건기인고제소서건립정상체외배층특이성Smad4조건성기인고제소서(C57BL/6소서계),실활Smad4재루선、정상체、각막화안검외배층적표체,채용상규조직학방법관찰기루선적형태학개변,동시Cre급Rosa26보도기인쌍전기인소서통과LacZ염색관찰루선발육과정중여동령야생형소서루선발육화형태적차별.매조지소사용6지동령소서혹소서배태진행비교.결과 LacZ염색현시,여잉15.0d적야생형상비,동태령Smad4기인고제소서배태잉가형성루선원아,단기명현단소；잉16.5d적야생형루선아이유분지,이변이형잉미견분지,부전단변원둔,지잉18.0d수유분지병출현선포,단기분지、선포대소화수목균명현소우야생형；조직해부학발현Smad4변이소서출생후기루선발육잉구완만,표현위기선체대소、분협급선포수목균교동령야생소서자현저감소,병자P7기출현점진성증가적색소급지방퇴적,지성숙기,선체완전피지방조직화색색소취대.결론 Smad4대우소서루선적정상발육유착중요적작용,병가능영향선체내색소화지방적대사.
Background Smad4,a key intracellular mediator in transforming growth factor-β (TGF-β)signaling,plays a critical role in the normal development of many tissues/organs.However,its functional role in the development of lacrimal gland has rarely been reported. Objective The aim of this study was to investigate the role that Smad4 may play in the development of lacrimal glands using Smad4 conditional knockout (CKO) mice( C57BL/6 mouse line), Methods Smad4 in lacrimal glands,as well as in the lens,cornea and ectoderm of the eyelids,was conditionally inactivated by the Pax6 promoter-driven Cre transgenic mice and Smad4 conditional gene mice,LacZ reporter was used to visualize the developing lacrimal gland by X-gal staining,and standard histological approaches were used to reveal morphological changes.Six or more mice or embryos in each group were used for comparisons at the same stage. Results LacZ staining showed that E15.0,Smad4 CKO mice could still develop primary lacrimal bud,but much shorter than the wild-type ones.At E16.5,the primary lacrimal bud in wild-type mice began branching,but no branching was found in Smad4 CKO mice except that the primary lacimal bud became blunt at the tip.At E18.0,although Smad4 CKO mice develop some acini,the branching and size and number of acini were obviously less than ones in Smad4 wild-type mice.Based on histological findings,lacrimal glands in Smad4 CKO mice developed slowly,and the size was considerably smaller,and the numbers of lobes as well as the numbers of acini were much fewer than those of Smad4 wild-type mice lacrimal glands at various stages.Pigment and adipose tissue were also observed within the lacrimal glands starting from P7 in Smad4 CKO mice and increased with age growing.Lacrimal glands in mutant adult mice were eventually replaced by adipose tissue and accumulation of pigments. Conclusions These results support the notion that Smad4 is essential for the normal development and maintenance of the mouse LG and may be involved in the metabolism of pigment and adipose tissue in LG.
