title: Comparative Gene Expression Analysis of the Coronal Pulp and Apical Pulp Complex in Human Immature Teeth.
abstract: BACKGROUND
  This study determined the gene expression profiles of the human coronal pulp (CP) and apical pulp complex (APC) with the aim of explaining differences in their functions.
  
  
  METHODS
  Total RNA was isolated from the CP and APC, and gene expression was analyzed using complementary DNA microarray technology. Gene ontology analysis was used to classify the biological function. Quantitative reverse-transcription polymerase chain reaction and immunohistochemical staining were performed to verify microarray data.
  
  
  RESULTS
  In the microarray analyses, expression increases of at least 2-fold were present in 125 genes in the APC and 139 genes in the CP out of a total of 33,297 genes. Gene ontology class processes found more genes related to immune responses, cell growth and maintenance, and cell adhesion in the APC, whereas transport and neurogenesis genes predominated in the CP. Quantitative reverse-transcription polymerase chain reaction and immunohistochemical staining confirmed the microarray results, with DMP1, CALB1, and GABRB1 strongly expressed in the CP, whereas SMOC2, SHH, BARX1, CX3CR1, SPP1, COL XII, and LAMC2 were strongly expressed in the APC.
  
  
  CONCLUSIONS
  The expression levels of genes related to dentin mineralization, neurogenesis, and neurotransmission are higher in the CP in human immature teeth, whereas those of immune-related and tooth development-related genes are higher in the APC.
authors.affiliation: Department of Pediatric Dentistry, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Soo-Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Pediatric Dentistry, Institute of Oral Health Science, Ajou University School of Medicine, Suwon, Republic of Korea.
authors.forename: Seunghye
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Conservative Dentistry, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Yooseok
authors.initials: Y
authors.lastname: Shin
authors.affiliation: Department of Pediatric Dentistry, Dental School, Kyung Hee University, Seoul, Republic of Korea.
authors.forename: Hyo-Seol
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Mijeong
authors.initials: M
authors.lastname: Jeon
authors.affiliation: Department of Pediatric Dentistry, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Seong-Oh
authors.initials: SO
authors.lastname: Kim
authors.affiliation: Division in Anatomy and Developmental Biology, Department of Oral Biology, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
authors.forename: Sung-Won
authors.initials: SW
authors.lastname: Cho
authors.affiliation: Department of Endodontics, University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors.forename: Nikita B
authors.initials: NB
authors.lastname: Ruparel
authors.affiliation: Department of Pediatric Dentistry, College of Dentistry, Yonsei University, Seoul, Republic of Korea; Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, Republic of Korea. Electronic address: songjs@yuhs.ac.
authors.forename: Je Seon
authors.initials: JS
authors.lastname: Song
mesh_terms: D000293:Adolescent; D000073883:CX3C Chemokine Receptor 1; D064092:Calbindin 1 / Q000235:genetics; D002135:Calcium-Binding Proteins / Q000235:genetics; D002448:Cell Adhesion / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D024082:Collagen Type XII / Q000235:genetics; D003782:Dental Pulp / Q000033:anatomy & histology / Q000166:cytology / Q000000981:diagnostic imaging / Q000254:growth & development*; D016326:Extracellular Matrix Proteins / Q000235:genetics; D005260:Female; D015870:Gene Expression; D020869:Gene Expression Profiling; D053823:Hedgehog Proteins / Q000235:genetics; D018398:Homeodomain Proteins / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007797:Laminin / Q000235:genetics; D008297:Male; D046228:Microarray Analysis / Q000379:methods; D055495:Neurogenesis / Q000235:genetics; D009805:Odontogenesis / Q000235:genetics*; D053495:Osteopontin / Q000235:genetics; D010750:Phosphoproteins / Q000235:genetics; D012313:RNA / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D019707:Receptors, Chemokine / Q000235:genetics; D011963:Receptors, GABA-A / Q000235:genetics; D056910:Republic of Korea; D009435:Synaptic Transmission / Q000235:genetics; D019227:Tooth Apex / Q000033:anatomy & histology / Q000166:cytology / Q000000981:diagnostic imaging / Q000254:growth & development*; D014074:Tooth Calcification / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D055815:Young Adult
chemical_list: C490667:BARX1 protein, human; C576498:CALB1 protein, human; D000073883:CX3C Chemokine Receptor 1; C095235:CX3CR1 protein, human; D064092:Calbindin 1; D002135:Calcium-Binding Proteins; D024082:Collagen Type XII; C513309:DMP1 protein, human; D016326:Extracellular Matrix Proteins; C546264:GABRB1 protein, human; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; C400567:LAMC2 protein, human; D007797:Laminin; D010750:Phosphoproteins; D019707:Receptors, Chemokine; D011963:Receptors, GABA-A; C509239:SHH protein, human; C476827:SMOC2 protein, human; C506895:SPP1 protein, human; D014157:Transcription Factors; D053495:Osteopontin; D012313:RNA
keywords: Apical pulp complex; complementary DNA microarray; coronal pulp; human immature teeth; immunohistochemical staining