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2014年2月14日 平成26年度（2014年度）3年次編入学（4月入学）合格者受験番号一覧
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2014年03月05日（水）16:00〜 "Actin-based motility of Vaccinia virus: unexpected insights into Arp2/3-driven actin polymerizationn" Dr. Michael Way (London Research Institute, UK Editor-in-Chief, Journal of Cell Science)
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【入試について】平成27年4月入学の編入学試験からの出願の要件について
平成27年4月入学の編入学試験より、願書とともにTOEICスコアの提出が必要となり、TOEICスコアが５５０点以上であることが出願の要件となりました。受験をお考えの方はご注意ください。
生命機能研究科入試委員会
入試に関する情報はこちら（随時更新）をご覧ください
生命機能研究科入試委員会
入試に関する情報はこちら（随時更新）をご覧ください
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平成27年度（2015年度）入学のための入試説明会
平成26年度大学院入試説明会の日程が決まりました。
平成26年4月19日（土）10：00-12：00
大阪大学吹田キャンパスコンベンションセンター
（ 平成24年度説明会の様子 平成23年度説明会の様子 ）
平成26年4月19日（土）10：00-12：00
大阪大学吹田キャンパスコンベンションセンター
（ 平成24年度説明会の様子 平成23年度説明会の様子 ）
【プログラム】
（午前の部）10：00-12：00
・研究科長挨拶
・入試説明
（午前の部）10：00-12：00
・研究科長挨拶
・入試説明
・カリキュラム説明
・質疑応答
・生命機能研究科教員自己紹介
（午後の部）13：00-
研究室訪問実施 （訪問を希望する研究室へ移動）
・生命機能研究科教員自己紹介
（午後の部）13：00-
研究室訪問実施 （訪問を希望する研究室へ移動）
後日、研究室訪問リスト情報を追加します。最終版は当日配付。
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2014年4月19日（土） 平成27年度（2015年度）入学のための入試説明会
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2014年03月10日（月）開催 "Flagellar number control in Salmonella enterica and Escherichia coli" Dr. Phillip Aldridge (Newcastle University)
【 Seminar Announcement 】
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Date/Time: March 10, 2014（Mon) Time:16:00-17:00
Place: 3F Seminar room, Nanobiology Building
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Title："Flagellar number control in Salmonella enterica and Escherichia coli"
Dr. Phillip Aldridge
(Senior Lecturer, Centre for Bacterial Cell Biology
Institute for Cell and Molecular Biosciences, Newcastle University)
----- Abstract -----------------------------------------
The bacterial cell surface contains numerous membrane spanning organelles carrying out a wide variety of functions. Many of these organelles act as clinically important virulence factors. In the bacterium Salmonella enterica serovar Typhimurium, one such organelle is the flagellum, required for motility.
Previously we have shown that the level of flagellation of cells in a population is influenced by nutrient concentration. A consequence of varying the availability of nutrients is a change in growth rate. In order to determine whether changes in flagellar abundance were dependent on growth rate, we have employed the use of a continuous culture system. Using this method allows us to alter the growth rate of a culture whilst keeping nutrient conditions constant.
Our results show that growth rate positively influences flagellar abundance in S. enterica. Interestingly, even at our faster growth rate we always observe a level of heterogeneity in the population with a proportion of cells remaining in a non-motile, Fla- state.
We have used our culture system with a library of flagellar mutants to determine what regulatory factors govern the variance in flagellar abundance. Our data suggests the regulation of flagellar abundance is positively regulated in response to growth rate via changes in flhDC expression.
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Host：Keiichi Namba (4625)
Email: keiichi@fbs.osaka-u.ac.jp
All members of FBS are invited to participate in this seminar.
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Date/Time: March 10, 2014（Mon) Time:16:00-17:00
Place: 3F Seminar room, Nanobiology Building
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Title："Flagellar number control in Salmonella enterica and Escherichia coli"
Dr. Phillip Aldridge
(Senior Lecturer, Centre for Bacterial Cell Biology
Institute for Cell and Molecular Biosciences, Newcastle University)
----- Abstract -----------------------------------------
The bacterial cell surface contains numerous membrane spanning organelles carrying out a wide variety of functions. Many of these organelles act as clinically important virulence factors. In the bacterium Salmonella enterica serovar Typhimurium, one such organelle is the flagellum, required for motility.
Previously we have shown that the level of flagellation of cells in a population is influenced by nutrient concentration. A consequence of varying the availability of nutrients is a change in growth rate. In order to determine whether changes in flagellar abundance were dependent on growth rate, we have employed the use of a continuous culture system. Using this method allows us to alter the growth rate of a culture whilst keeping nutrient conditions constant.
Our results show that growth rate positively influences flagellar abundance in S. enterica. Interestingly, even at our faster growth rate we always observe a level of heterogeneity in the population with a proportion of cells remaining in a non-motile, Fla- state.
We have used our culture system with a library of flagellar mutants to determine what regulatory factors govern the variance in flagellar abundance. Our data suggests the regulation of flagellar abundance is positively regulated in response to growth rate via changes in flhDC expression.
--------------------------------------------------------------
Host：Keiichi Namba (4625)
Email: keiichi@fbs.osaka-u.ac.jp
All members of FBS are invited to participate in this seminar.
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2014年03月11日（火）更新 学生海外活動レポートを追加しました。
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2014年03月14日（金）開催 "Dynamics of population responses in the cat visual cortex" Dr. Andrea Benucci (RIKEN BSI)
Dr. Andrea Benucci (RIKEN BSI)
Date: March 14, 2013, 16:00~
Place: CiNet 1F Conference Room A
Title: Dynamics of population responses in the cat visual cortex
Abstract:
Information processing in the cortex is mediated by the coordinated activity of large populations of neurons. However, the computational rules used by neurons to process information are still poorly understood. To address this problem I focus on the visual system, specifically on the cat primary visual cortex (V1), where I study how attributes of visual stimuli are processed by large ensembles of neurons. My goal is to find a simple set of rules that describes the encoding of sensory signals by neuronal populations under different stimulus conditions. The experimental tools I use to record spontaneous and visually induced activity in V1 are based on multi-electrode recordings, voltage-sensitive dye imaging, and imaging of intrinsic signals. A particularly successful approach has been to describe population responses in terms of standing and propagating waves of activity. I will discuss the implications of these results for the rules of sensory processing and their dependence on stimulus attributes.
URL for Dr Benucci's web site at RIKEN BSI:
Andrea ベヌッチ , Benucci アンドレア, Ph.D.
- 脳の知覚認識の神経機構を解明する。
http://www.brain.riken.jp/jp/faculty/details/80
Date: March 14, 2013, 16:00~
Place: CiNet 1F Conference Room A
Title: Dynamics of population responses in the cat visual cortex
Abstract:
Information processing in the cortex is mediated by the coordinated activity of large populations of neurons. However, the computational rules used by neurons to process information are still poorly understood. To address this problem I focus on the visual system, specifically on the cat primary visual cortex (V1), where I study how attributes of visual stimuli are processed by large ensembles of neurons. My goal is to find a simple set of rules that describes the encoding of sensory signals by neuronal populations under different stimulus conditions. The experimental tools I use to record spontaneous and visually induced activity in V1 are based on multi-electrode recordings, voltage-sensitive dye imaging, and imaging of intrinsic signals. A particularly successful approach has been to describe population responses in terms of standing and propagating waves of activity. I will discuss the implications of these results for the rules of sensory processing and their dependence on stimulus attributes.
URL for Dr Benucci's web site at RIKEN BSI:
Andrea ベヌッチ , Benucci アンドレア, Ph.D.
- 脳の知覚認識の神経機構を解明する。
http://www.brain.riken.jp/jp/faculty/details/80
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2014年03月19日（水）16:00〜17:00開催 「研究の表と裏：大脳生理学者の世界と外の社会」板東武彦先生（新潟大学名誉教授）
講演者：板東武彦先生
新潟大学名誉教授
（独）科学技術振興さきがけ「脳情報の解読と制御」研究領域技術参事
（独）産業技術研究所 客員研究員
タイトル： 研究の表と裏： 大脳生理学者の世界と外の社会
日時：2014年3月19日（水） 16:00-17:00
場所：大阪大学 吹田キャンパス ナノバイオロジー棟 3階セミナー室
板東武彦先生は、約40年前に大阪大学基礎工学部生物工学科に在籍され、その後、山梨医科大学を経て新潟大学医学部生理学教室を主宰されました。 その間、眼球運動の神経制御機構に取り組まれ、大脳皮質での支配領域の決定から制御様式を明らかにされてきました。新潟大学退官後も、ご研究を続 けられ、映像がヒトに及ぼす作用や映像の国際標準策定にも携わっておられます。同時に、科学技術振興機構さきがけ技術参事として、我が国の研究体 制や研究費分配にも関わっておられます。ご講演では、これまでの研究人生と研究支援のお話をして下さいます。
新潟大学名誉教授
（独）科学技術振興さきがけ「脳情報の解読と制御」研究領域技術参事
（独）産業技術研究所 客員研究員
タイトル： 研究の表と裏： 大脳生理学者の世界と外の社会
日時：2014年3月19日（水） 16:00-17:00
場所：大阪大学 吹田キャンパス ナノバイオロジー棟 3階セミナー室
板東武彦先生は、約40年前に大阪大学基礎工学部生物工学科に在籍され、その後、山梨医科大学を経て新潟大学医学部生理学教室を主宰されました。 その間、眼球運動の神経制御機構に取り組まれ、大脳皮質での支配領域の決定から制御様式を明らかにされてきました。新潟大学退官後も、ご研究を続 けられ、映像がヒトに及ぼす作用や映像の国際標準策定にも携わっておられます。同時に、科学技術振興機構さきがけ技術参事として、我が国の研究体 制や研究費分配にも関わっておられます。ご講演では、これまでの研究人生と研究支援のお話をして下さいます。
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2014年03月26日（水） 「RNA in situ ハイブリダイゼーションアッセイによる迅速なターゲットバリデーションとバイオマーカー開発」Christopher Bunker, Ph.D. (Advanced Cell Diagnostics, Inc)
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2014年03月19日（水）更新 学生海外活動レポートを追加しました。
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2014年03月19日（水）14:30〜16:00開催 "How the parietal cortex creates an accurate representation of visual space for action and perception despite a constantly moving eye" Prof. Michael E. Goldberg (Columbia University College of Physicians and Surgeons)
Speaker: Prof. Michael E. Goldberg
Date/Time: March 19 (Wed), 14:30 - 16:00
Place: CiNet Building, Conference Room A&B
Title: "How the parietal cortex creates an accurate representation of visual space for action and perception despite a constantly moving eye."
Abstract: In order to link perception and action the brain must have a spatially accurate representation of the visual world, so it can generate actions appropriate to the objects it perceives. The only way visual information enters the eye is through the retina, which moves constantly between brief fixations. The retinal location of targets for action is not useful for calculating movements to acquire those targets. Two strategies have been postulated to calculate the accurate location of movement targets: Helmholtz suggested that the brain knows the command to move the eye, and therefore can use that motor command to update the sensory representation. Hering suggested that the brain can calculate accurate target location if it knows the position of the eye in the world. In keeping with Helmholtz's suggestion, the receptive fields of parietal neurons are remapped around the time of an eye movement, so that a neuron will respond to a stimulus not in its receptive field as determined in a fixation task if that stimulus will be moved into the receptive field by a saccade. This remapping is accomplished by a stretching of the receptive field along the trajectory of the saccade, so that a stimulus that flashes in an intermediate location crossed by the receptive field during the saccade, but not in either the current or future receptive fields as defined by the saccade will drive the cell briefly around the time of the saccade. The receptive field stretches like a rubber band: the intermediate location drives the cell before the future receptive field does. In keeping with Hering's suggestion, there is a representation of eye position in somatosensory cortex. Neurons in parietal cortex have their visual responses modulated by the position of the eye in the orbit (Andersen and Mountcastle, 1983) and this can be used to calculated target position in space (Zipser and Andersen, 1988). The somatosensory cortex signal lags eye position by 60 ms, and the eye position modulation of visual responses lags eye position by at least 150 ms, and is dependent upon somatosensory cortex. Thus the position signal is too slow to do the job for stimuli that flash briefly around the time of a saccade, but could be used to calibrate the efference copy signal.
Michael E. Goldberg M.D.
David Mahoney Professor of Brain and Behavior in the Departments of Neuroscience, Neurology, Psychiatry, and Ophthalmology
Columbia University College of Physicians and Surgeons
Website: mahoney.cpmc.columbia.edu/goldberglab
Date/Time: March 19 (Wed), 14:30 - 16:00
Place: CiNet Building, Conference Room A&B
Title: "How the parietal cortex creates an accurate representation of visual space for action and perception despite a constantly moving eye."
Abstract: In order to link perception and action the brain must have a spatially accurate representation of the visual world, so it can generate actions appropriate to the objects it perceives. The only way visual information enters the eye is through the retina, which moves constantly between brief fixations. The retinal location of targets for action is not useful for calculating movements to acquire those targets. Two strategies have been postulated to calculate the accurate location of movement targets: Helmholtz suggested that the brain knows the command to move the eye, and therefore can use that motor command to update the sensory representation. Hering suggested that the brain can calculate accurate target location if it knows the position of the eye in the world. In keeping with Helmholtz's suggestion, the receptive fields of parietal neurons are remapped around the time of an eye movement, so that a neuron will respond to a stimulus not in its receptive field as determined in a fixation task if that stimulus will be moved into the receptive field by a saccade. This remapping is accomplished by a stretching of the receptive field along the trajectory of the saccade, so that a stimulus that flashes in an intermediate location crossed by the receptive field during the saccade, but not in either the current or future receptive fields as defined by the saccade will drive the cell briefly around the time of the saccade. The receptive field stretches like a rubber band: the intermediate location drives the cell before the future receptive field does. In keeping with Hering's suggestion, there is a representation of eye position in somatosensory cortex. Neurons in parietal cortex have their visual responses modulated by the position of the eye in the orbit (Andersen and Mountcastle, 1983) and this can be used to calculated target position in space (Zipser and Andersen, 1988). The somatosensory cortex signal lags eye position by 60 ms, and the eye position modulation of visual responses lags eye position by at least 150 ms, and is dependent upon somatosensory cortex. Thus the position signal is too slow to do the job for stimuli that flash briefly around the time of a saccade, but could be used to calibrate the efference copy signal.
Michael E. Goldberg M.D.
David Mahoney Professor of Brain and Behavior in the Departments of Neuroscience, Neurology, Psychiatry, and Ophthalmology
Columbia University College of Physicians and Surgeons
Website: mahoney.cpmc.columbia.edu/goldberglab
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2014年03月20日（木）17:00〜19:00開催 "Neural Correlates of Active Vision" Junji Ito (Juelich Research Centre and JARA, Juelich, Germany)
Title: Neural Correlates of Active Vision
Time: March 20th (Thursday) 17:00~19:00
Place: CiNet 1F Main Seminar RoomA
Speaker: Junji Ito
Affiliation: Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6), Juelich Research Centre and JARA, Juelich, Germany
Abstract: Recent studies have emphasized functional roles of oscillatory neuronal activities during visual processing in natural conditions, such as free viewing of complex natural scenes or watching of natural movies. While a number of functionally relevant frequency components has been reported in multiple frequency bands, little is known about whether the components in different frequency bands are independent or not, and if not, how they interact with each other. We examined this phenomenon in local field potential (LFP) signals obtained from the primary visual cortex of capuchin monkeys freely viewing still images of natural scenes. We identified eye movement related changes with respect to power and phase of the LFP signal in four dominant frequency bands: delta-theta (2-4 Hz), alpha-beta (10-13 Hz), low-gamma (20-40 Hz), and high-gamma (>100 Hz). We found that the phase of the delta-theta band component was found to be entrained to the rhythm of the repetition of voluntary saccades, and that modulation of the power in the alpha-beta and low-gamma bands was locked to the onset of saccades. Furthermore, the strength of the power modulation in the alpha-beta and low-gamma frequency bands was positively correlated with the strength of the phase-locking of the delta-theta oscillations. These results suggest cross-frequency interactions in the form of phase-amplitude coupling between the slow (delta-theta) and the faster (alpha-beta and low gamma) oscillations. We also found that the timing of neuronal spikes evoked by visual fixations during the free viewing was phase-locked to the fast oscillations. Such cross-frequency interaction may provide a general mechanism for coordination of motor action, which occurs on the timescale of several hundred milliseconds, and spiking activity, occurring on the timescale of milliseconds, during active sensing behaviors.
Time: March 20th (Thursday) 17:00~19:00
Place: CiNet 1F Main Seminar RoomA
Speaker: Junji Ito
Affiliation: Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6), Juelich Research Centre and JARA, Juelich, Germany
Abstract: Recent studies have emphasized functional roles of oscillatory neuronal activities during visual processing in natural conditions, such as free viewing of complex natural scenes or watching of natural movies. While a number of functionally relevant frequency components has been reported in multiple frequency bands, little is known about whether the components in different frequency bands are independent or not, and if not, how they interact with each other. We examined this phenomenon in local field potential (LFP) signals obtained from the primary visual cortex of capuchin monkeys freely viewing still images of natural scenes. We identified eye movement related changes with respect to power and phase of the LFP signal in four dominant frequency bands: delta-theta (2-4 Hz), alpha-beta (10-13 Hz), low-gamma (20-40 Hz), and high-gamma (>100 Hz). We found that the phase of the delta-theta band component was found to be entrained to the rhythm of the repetition of voluntary saccades, and that modulation of the power in the alpha-beta and low-gamma bands was locked to the onset of saccades. Furthermore, the strength of the power modulation in the alpha-beta and low-gamma frequency bands was positively correlated with the strength of the phase-locking of the delta-theta oscillations. These results suggest cross-frequency interactions in the form of phase-amplitude coupling between the slow (delta-theta) and the faster (alpha-beta and low gamma) oscillations. We also found that the timing of neuronal spikes evoked by visual fixations during the free viewing was phase-locked to the fast oscillations. Such cross-frequency interaction may provide a general mechanism for coordination of motor action, which occurs on the timescale of several hundred milliseconds, and spiking activity, occurring on the timescale of milliseconds, during active sensing behaviors.
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2014年03月27日（木）16:00〜17:30開催 "The spliceosome: the active site and its evolutionary origin"長井潔先生（ケンブリッジ大学MRC分子生物学研究所グループリーダー）
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2014年03月31日（月）16:00〜17:00開催 "What structural dissection of bacterial flagellar motors in situtells us about molecular mechanism and evolution" Prof. Morgan Beeby (Department of Life Sciences, Imperial College London)
【 Seminar Announcement 】
----------------------------------------
Date/Time: March 31, 2014（Mon) Time:16:00-17:00
Place: 3F Seminar room, Nanobiology Building
----------------------------------------
Title："What structural dissection of bacterial flagellar motors in situ
tells us about molecular mechanism and evolution"
Prof. Morgan Beeby
(Department of Life Sciences, Imperial College London)
----- Abstract -----------------------------------------
Understanding how proteins act as nanomachines is of critical importance. An excellent case-study in protein nanomachinery is the bacterial flagellar motor, which both spins the flagellar filament to propel the cell to favourable environments, and self-assembles using an integral "type III secretion system". To study these two mechanisms, we have employed electron cryo-tomography to produce 3-D images of flagellar motors in situ at resolutions sufficient to resolve individual proteins. The foundation of our studies was a comparative imaging study of flagellar motors from a range of phylogenetically diverse bacteria that revealed widespread elaborations upon the 'normal' Salmonella enterica or Escherichia coli motors. This study enabled us to augment our comparative electron cryo-tomography approach with genetic screens and bioinformatics to pinpoint the location of the two energy-transducing proteins involved in type III secretion self-assembly, enabling us to develop a working model on the mechanism of type III secretion. Our studies also revealed variations in the torque-generating components between motors from different species, enabling us to correlate structure with function and hypothesize about evolution of additional complexity seen in some species. In conclusion, electron cryo-tomography enables us to brides scales from the organism to atomic structure of proteins and construct mechanistic hypotheses regarding the function of macromolecular machinery.
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Date/Time: March 31, 2014（Mon) Time:16:00-17:00
Place: 3F Seminar room, Nanobiology Building
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Title："What structural dissection of bacterial flagellar motors in situ
tells us about molecular mechanism and evolution"
Prof. Morgan Beeby
(Department of Life Sciences, Imperial College London)
----- Abstract -----------------------------------------
Understanding how proteins act as nanomachines is of critical importance. An excellent case-study in protein nanomachinery is the bacterial flagellar motor, which both spins the flagellar filament to propel the cell to favourable environments, and self-assembles using an integral "type III secretion system". To study these two mechanisms, we have employed electron cryo-tomography to produce 3-D images of flagellar motors in situ at resolutions sufficient to resolve individual proteins. The foundation of our studies was a comparative imaging study of flagellar motors from a range of phylogenetically diverse bacteria that revealed widespread elaborations upon the 'normal' Salmonella enterica or Escherichia coli motors. This study enabled us to augment our comparative electron cryo-tomography approach with genetic screens and bioinformatics to pinpoint the location of the two energy-transducing proteins involved in type III secretion self-assembly, enabling us to develop a working model on the mechanism of type III secretion. Our studies also revealed variations in the torque-generating components between motors from different species, enabling us to correlate structure with function and hypothesize about evolution of additional complexity seen in some species. In conclusion, electron cryo-tomography enables us to brides scales from the organism to atomic structure of proteins and construct mechanistic hypotheses regarding the function of macromolecular machinery.
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2014年04月03日（木）14:00〜15:00開催 "Loss of developmental regulatory genes in mammalian evolution: molecular phylogenetics for developmental biology" Dr. Shigehiro Kuraku (Genome Resource and Analysis Unit, RIKEN CDB)
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第97回生命機能研究科研究交流会2014年4月21日（月）16時～18時特別講演：椛島健治 先生 （京大医学研究科 皮膚科・准教授）/菊田順一 先生（阪大医学系研究科 免疫細胞生物学・助教）
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2014年04月01日（火）16:00〜17:00開催 「古生物の形を復元する」岡本隆先生（愛媛大学大学院理工学研究科）
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第7代 研究科長 仲野 徹 挨拶
めざせ！『おもろい』生命機能研究
大阪大学 大学院生命機能研究科 研究科長
科学は、その歴史が示すように、哲学にはじまって、博物学的な研究から多くの分野へとわかれてきました。意図的というよりは自然に細分化してきたものであって、生命科学もその一分野にすぎません。しかし、生命というものは、わたしたちの存在そのものであり、とりわけ重要な一分野です。
わたしたちの研究科は、生命機能という名がしめすとおり、『生命のはたらき』をさぐることを目的にした研究科です。それぞれの研究者が、さまざまな生物を対象に、分子から細胞、臓器そして個体にいたるまで、さまざまなスケールにおける生命現象を解析しています。
そのためには、生物学や医学だけではなく、化学、さらには物理学や数学、電子工学や通信工学にいたるまで、非常に多岐にわたる方法論が必要です。わたしたちの研究科は、それらの分野を融合することにより、あたらしい視点から、生命というものをもっと詳しく知りたい、誰もがなしえなかったような高いレベルで生物のはたらきを知りたい、という目的で平成１４年に設立されました。
『融合』といっても、ほんとうにそんなことができるのか、と思われるかもしれません。分野がわかれていったのは必然でしたが、こんどは意図的に、生命を知るという目的のため、いわば強引に融合させようというのですから、たしかに容易なことではありません。しかし、いろいろなことがわかりつつある今だからこそ可能になってきたともいえるのです。
けっして大きな研究科ではありませんので、研究科のメンバーだけですべてのことをまかなうことはできません。幸いなことに、情報通信研究機構などとの協力で発足した脳情報通信融合研究センター（CiNet）や理化学研究所の生命システム研究センター（QBiC）が近在していますので、それらのセンターなどと密接な関係をとりながら、幅広い意味での新しい生命科学研究をおこなっています。
いきなり融合といっても難しすぎるかもしれません。しかし、わたしたちの研究科は『おもろい研究』こそが大事であると考えています。たとえば、ちょっと違った分野の研究をおもしろがることから始めてみてはどうでしょう？そうすると、どの分野の人であっても、生命科学を楽しむことができるはずです。そして、そのおもしろさがどんどん広がっていくはずです。生命に興味をもって『おもろい研究』をめざす人がひとりでもたくさんあつまってくれる場所。わたしたちは、そういう研究科をめざしています。
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世界に先駆け発見！神経細胞の個性化と精緻な回路形成に必要な 発生初期のDNA修飾メカニズムを解明
図１．クラスター型プロトカドヘリン（cPcdh）遺伝子群
α、β、γの３つの遺伝子クラスターにより、５８種類の遺伝子が縦列したゲノム構造をしている（上図）。対立遺伝子ごとに独立して制御されており（下左図）、個々の神経細胞ごとに異なる遺伝子を発現することから、神経細胞の個性化に関わっていると考えられている（下右図）。
図２．cPcdh遺伝子群は発生初期にDNAメチル化される
cPcdh遺伝子のプロモーター領域は胎生3.5日目の胎仔ではほとんどDNAメチル化されていないが、発生が進んだ胎生9.5日目ではDNA鎖ごとに異なるメチル化パターンが形成されている。一方、Dnmt3b欠損マウスではほとんどメチル化されない。メチル化レベルをパーセントで表示。（横棒：DNA 一本鎖、白丸：非メチル化シトシン、黒丸：メチル化シトシン）。
図３．Dnmt3b依存的なメチル化はプルキンエ細胞の樹状突起のパターン形成を制御する
（上図）Dnmt3b欠損iPS細胞の樹立とキメラマウスの作製。（下左図）野生型およびDnmt3b欠損プルキンエ細胞の３次元構築像とトレース像。Dnmt3b欠損により樹状突起の分枝の異常が認められる（矢印）。スケールバー 50 μm。（下右図）拡大図。スケールバー 10 μm。
図４．Dnmt3b依存的なメチル化は個々の神経細胞におけるcPcdh遺伝子群のランダムな発現を制御する
（上図）キメラマウスの小脳を分散後、GFP陽性（Dnmt3b欠損;矢印）および陰性（野生型；矢頭）プルキンエ細胞のピックアップを行う。スケールバー 100 μm。（下図）単一プルキンエ細胞（Pcp2陽性）におけるPcdh-α遺伝子群の発現パターン。Dnmt3b欠損により単一細胞において発現するPcdh-α遺伝子の数が増加する。
図５．まとめ
胎生3.5日目の胚である胚盤胞においてcPcdhのプロモーター領域はメチル化されていない（白丸）が、初期の胚発生期にDnmt3bによって細胞ごとに異なるメチル化パターンが形成される（黒丸）。それにより、後に産生される個々の神経細胞において、細胞ごとに異なるcPcdh遺伝子がエンハンサー（赤丸）によって選択されて発現する。一方でDnmt3b欠損細胞はメチル化されず、個々の神経細胞ですべてのcPcdh遺伝子を発現してしまうため、神経細胞の個性化が起きない。
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