干细胞之家 - 中国干细胞行业门户第一站
标题:
New stem cell maintenance protein found
[打印本页]
作者:
韩雪娜
时间:
2008-12-30 23:25
标题:
New stem cell maintenance protein found
日期: 2002-12-02 今日/总浏览: 1/696
0 r# }8 s" |8 C5 o
+ L \2 c+ s7 Q# `5 ^
, I5 f# K9 y8 }5 \1 b% _2 `% s
. F; z# A% Z4 Q1 s, h) {% W( @2 ]
3 h4 X' Q2 s0 T1 I4 K
" U& b3 S3 W' k! d; c+ `2 N- w
4 `4 R% [' G" \/ i5 C7 z
Ronald D.G. McKay, Ph.D.
: {! c, F% y( K% C* q" O5 P
Scientistshaveidentifiedacritical,newstemcellprotein?amarkedadvanceintheelucidationofthemolecularblueprintofstemcells.
4 @( R: u" r" m: @# H6 g$ O0 G
Drs.RobertTsaiandRonaldMcKayattheNIHhavediscoveredanovelgene,callednucleostemin,whoseencodedproteinisnecessaryformaintainingtheproliferativecapacityofembryonicandadultstemcells,andpossiblysometypesofcancercells.TheirreportispublishedintheDecember1issueofthescientificjournalGenes&Development.
9 a! d- D3 T7 d5 K7 _; q
Embryonicstemcellsarepluripotentprogenitorcellsthatcandifferentiateintoallofthecelltypesofthebody.Adultstemcells,incontrast,havealessversatilepotential:Theirdifferentiationisgenerallyrestrictedtothecelltypesofaspecifictissue(althoughrecentworkhasexpandedthepreviouslyknownrangeofadultstemcelldifferentiationpotential).
0 g h V1 h* C; Q G$ [% A
Akeyfeatureofbothembryonicandadultstemcellsistheircapacityforself-renewalaswellasdifferentiation?ensuringthataconstantpoolofundifferentiatedstemcellsalwaysexists.Drs.TsaiandMcKayhaveidentifiednucleosteminasacriticalregulatorofthisdelicatebalance.
! n0 k) a( ~' \& _8 N4 O
Drs.TsaiandMcKayoriginallyidentifiednucleosteminasaproteinabundantlyexpressedinratCNS(centralnervoussystem)stemcellsthatismarkedlydown-regulatedduringdifferentiation,suggestingapossibleroleinstemcellmaintenance.Theresearcherswentontoshowthatnucleosteminisexpressedinvariousadultandembryonicstemcellpopulations,aswellasinsomehumancancercelllines,andthatitsexpressionisconsistentlyturned-offduringthedifferentiationofstemcellsintomorespecializedcelltypes.
8 {4 s9 p x. }
UsingtheRNAigenesilencingmethod,Drs.TsaiandMcKaydisruptednormalnucleosteminexpressionpatternsinrodentCNSstemcellsandhumanosteosarcomacancercells.Theyfoundthattheaberrantdown-regulationofnucleostemininthesecellscausedadecreaseincellproliferation,suggestingthattheexpressionofnucleosteminisrequiredforstemcell--andsomecancercell--proliferation.
! H |2 A* X) G* Y8 W$ r7 ~8 V* q
Althoughtheprecisemechanismofnucleosteminactionisnotyetfullyunderstood,theidentificationofagenewhoseproteinproductspecificallypromotestheproliferationofstemcellsandsomecancercellshasimportantclinicalimplicationsforboththeuseofstemcellsinregenerativemedicineaswellasthetreatmentofcancer.AsDr.Tsaiexplains,Thecharacterizationofnucleosteminsuggeststhatauniqueprimitivestateissharedbybothstemcellsandcancercelllines.Theidentificationofcommonmoleculessharedbybothstemcellsandcancercellsmayfacilitatethediscoveryofself-renewingpopulationswithinagiventumorbyevaluatingtheirexpressionlevels.Perhaps,inthefuture,targetingthesecellswillachieveabettertherapeuticoutcome.
5 p( b4 `! ]& l6 o: R/ a
2 p X7 s. `2 M3 b3 Z" ?+ Z, F
7 D6 x+ K" P, { p0 k% g. q2 f
, f. u' l4 t( s" [ G k, ^
& ~- q+ J. X+ x1 x3 u
. [' |5 M$ @: b! c5 T
作者:
5 Q/ [9 E9 ]% y( t$ p* V( @
来源: Cold Spring Harbor Laboratory
4 C+ m9 e P) z- ~
发布者: 刘斌
欢迎光临 干细胞之家 - 中国干细胞行业门户第一站 (http://www.stemcell8.cn/)
Powered by Discuz! X1.5