Objectives: Previous data has reported similarity between human brain and testis gene expression patterns. Brain is the most important tissue in human speciation. Hence, it means that human testis could also play a crucial role in human speciation if these two tissues exhibit similar gene expression patterns. However, previous reports were based on only limited and scattered data. Determining the large scale anatomy of gene expression patterns of various human tissues could draw a more convincing conclusion, and better our understanding of the correlation/inter-correlation among different tissues. Furthermore, it could also provide a clue for evolutionary study. Methods: To obtain gene expression information for large-scale data analysis, expression data of 760 Unigenes in seventeen human tissues (liver, lung, testis, brain, ovary, uterus, colon, stomach, heart, eye, kidney, spleen, gall bladder, breast, thymus, prostate and pancreas) were retrieved by DDD (differential digital display) analysis, and this expression data was subjected to clustering analysis. These Unigenes represent a wide range of genes classified according to their characterization and function. Results: Among the 17 tissues, the highest similarity in gene expression patterns was between human brain and testis, based on DDD and clustering analysis. Genes contributing to the similarity include ribosomal protein (RP) genes as well as genes involved in transcription, translation and cell division. Conclusions: Present results provide evidence to support the proposal that human testis and brain share the highest similarity of gene expression patterns. The implications of the similarity regarding that both brain and testis contributed to human speciation are discussed.   

1.
Audic S, Claverie JM: The significance of digital gene expression profiles. Genome Res 7:986–995 (1997).
2.
Bortoluzzi S, Alessi FD, Romualdi C, Danieli GA: The human adult skeletal muscle transcriptional profile reconstructed by a novel computational approach. Genome Res 10:344–349 (2000).
3.
Bortoluzzi S, Alessi FD, Romualdi C, Danieli GA: Differential expression of genes coding for ribosomal proteins in different human tissues. Bioinformatics 17:1152–1157 (2001).
4.
Graves JA: From brain determination to testis determination: evolution of the mammalian sex-determining gene. Reprod Fertil Dev 13:665–672 (2001).
5.
Bliss El, Frischat A, Samuels L: Links brain and testicular function. Life Sci I 11:231–238 (1972).
6.
Bostrom K, Brun A: Testicular changes in association with malformation of the central nervous system and mental retardation. Acta Pathol Microbiol Scand (A) 79:249–256 (1971).
7.
Brands A, Munzel PA, Bock KW: In situ hybridization studies of UDP-glucuronosyltransferase UGT1A6 expression in rat testis and brain. Biochem Pharmacol 59:1441–1444 (2000).
8.
Denis D, Adam SW: The evolution of “bricolage”. Trend Genet 14:54–59 (1998).
9.
Dragatsis I, Levine MS, Zeitlin S: Inactivation of Hdh in the brain and testis results in progressive neurodegeneration and sterility in mice. Nature Genet 26:300–306 (2000).
10.
Enard W, Khaitovich P, Klose J, Zollner S, Heissig F, Giavalisco P, Nieselt-Struwe K, Muchmore E, Varki A, Ravid R, Doxiadis GM, Bontrop RE, Paabo S: Intra- and interspecific variation in primate gene expression patterns. Science 296:340–343 (2002).
11.
Escriva H, Rodriguez-Pena A, Vallejo CG: Expression of mitochondrial genes and of the transcription factors involved in the biogenesis of mitochondria Tfam, NRF-1 and NRF-2, in rat liver, testis and brain. Biochimie 81:965–971 (1999).
12.
Fisher EM, Beer-Romero P, Brown LG, Ridley A, McNeil JA, Lawrence JB, Willard HF, Bieber FR, Page DC: Homologous ribosomal protein genes on the human X and Y chromosomes: escape from X inactivation and possible implications for Turner syndrome. Cell 63:1205–1218 (1990).
13.
Gerendai I, Toth IE, Boldogkoi Z, Medveczky I, Halasz B: Central nervous system structures labelled from the testis using the transsynaptic viral tracing technique. J Neuroendocrinol 12:1087–1095 (2000).
14.
Ghabriel MN, Lu JJ, Hermanis G, Zhu C, Setchell BP: Expression of a blood-brain barrier-specific antigen in the reproductive tract of the male rat. Reproduction 123:389–397 (2002).
15.
Gregory DS: Pieces of the puzzle: expressed sequence tags and the catalog of human genes. J molec Med 75:694–698 (1997).
16.
Gu J, Gu X: Induced gene expression in human brain after the split from chimpanzee. Trends Genet 19:63–65 (2003).
17.
Han JR, Gu W, Hecht NB: Testis-brain RNA-binding protein, a testicular translational regulatory RNA-binding protein, is present in the brain and binds to the 3′ untranslated regions of transported brain mRNAs. Biol Reprod 53:707–717 (1995).
18.
Ibberson M, Riederer BM, Uldry M, Guhl B, Roth J, Thorens B: Immunolocalization of GLUTX1 in the testis and to specific brain areas and vasopressin-containing neurons. Endocrinology 143:276–284 (2002).
19.
Inge-Vechtomov SG: A possible role of genetic translation ambiguity in evolution. Mol Biol (Mosk) 36:268–76 (2002).
20.
Jacob F: Evolution and tinkering. Science 196:1161–1166 (1977).
21.
Kitamura K, Yanazawa M, Sugiyama N, Miura H, Iizuka-Kogo A, Kusaka M, Omichi K, Suzuki R, Kato-Fukui Y, Kamiirisa K, Matsuo M, Kamijo S, Kasahara M, Yoshioka H, Ogata T, Fukuda T, Kondo I, Kato M, Dobyns WB, Yokoyama M, Morohashi K: Mutation of ARX causes abnormal development of forebrain and testes in mice and X-linked lissencephaly with abnormal genitalia in humans. Nature Genet 32:359–369 (2002).
22.
Kondoh N, Schweinfest CW, Henderson KW, Papas TS: Diffenetial expression of S19 ribosomal protein, laminin-binding protein, and human lymphocyte antigen class I messenger RNAs associated with colon carcinoma progression and differentiation. Cancer Res 52:791–796 (1992).
23.
Lewis R: Human Genetics Concepts and Applications, 3rd Ed, WCB (McGraw-Hill, New York 1999).
24.
Maeda K, Inui S, Tanaka H, Sakaguchi N: A new member of the alpha4-related molecule (alpha4-b) that binds to the protein phosphatase 2A is expressed selectively in the brain and testis. Eur J Biochem 264:702–706 (1999).
25.
Marazziti D, Gallo A, Golini E, Matteoni R, Tocchini-Valentini GP: Molecular cloning and chromosomal localization of the mouse Gpr37 gene encoding an orphan G-protein-coupled peptide receptor expressed in brain and testis. Genomics 53:315–324 (1998).
26.
Mayer H, Bauer H, Breuss J, Ziegler S, Prohaska R: Characterization of rat LANCL1, a novel member of the lanthionine synthetase C-like protein family, highly expressed in testis and brain. Gene 269:73–80 (2001).
27.
Muslimov IA, Lin Y, Heller M, Brosius J, Zakeri Z, Tiedge H: A small RNA in testis and brain: implications for male germ cell development. J Cell Sci 115:1243–1250 (2002).
28.
Ouimet T, Facchinetti P, Rose C, Bonhomme MC, Gros C, Schwartz JC: Neprilysin II: A putative novel metalloprotease and its isoforms in CNS and testis. Biochem biophys Res Commun 271:565–570 (2000).
29.
Pascal JM, Chennathukuzhi VM, Hecht NB, Robertus JD: Mouse testis-brain RNA-binding protein (TB-RBP): expression, purification and crystal X-ray diffraction. Acta Crystallogr D Biol Crystallogr 57:1692–1694 (2001).
30.
Pennisi E: Primate evolution gene activity clocks brain’s fast evolution. Science 296:233–235 (2002).
31.
Peterson LE: CLUSFAVOR 5.0: hierarchical cluster and principal-component analysis of microarray-based transcriptional profiles. Genome Biol 3:SOFTWARE0002 (2002).
32.
Reik W, Santos F, Dean W: Mammalian epigenomics: reprogramming the genome for development and therapy. Theriogenology 59:21–32 (2003).
33.
Sahin U, Koslowski M, Tureci O, Eberle T, Zwick C, Romeike B, Moringlane JR, Schwechheimer K, Feiden W, Pfreundschuh M: Expression of cancer testis genes in human brain tumors. Clin Cancer Res 6:3916–3922 (2000).
34.
Silverman GL, Qin K, Moore RC, Yang Y, Mastrangelo P, Tremblay P, Prusiner SB, Cohen FE, Westaway D. Doppel is an N-glycosylated, glycosylphosphatidylinositol-anchored protein. Expression in testis and ectopic production in the brains of Prnp(0/0) mice predisposed to Purkinje cell loss. J biol Chem 275:26834–26841 (2000).
35.
Stanton JL, Macgregor AB, Green DPL: Using expressed sequence tag database to identify ovarian genes of interest. Mol Cell Endocrin 191:11–14 (2002).
36.
Warner JR, Nierras CR: Trapping human ribosomal protein genes. Genome Res 8:419–421 (1998).
37.
Wilda M, Bachner D, Zechner U, Kehrer-Sawatzki H, Vogel W, Hameister H: Do the constraints of human speciation cause expression of the same set of genes in brain, testis, and placenta? Cytogenet Cell Genet 91:300–302 (2000).
38.
Wu XQ, Petrusz P, Hecht NB. Testis-brain RNA-binding protein (Translin) is primarily expressed in neurons of the mouse brain. Brain Res 819:174–178 (1999).
39.
Yamamoto H, Ochiya T, Takahama Y, Ishii Y, Osumi N, Sakamoto H, Terada M: Detection of spatial localization of Hst-1/Fgf-4 gene expression in brain and testis from adult mice. Oncogene 19:3805–3810 (2000).
© 2003 S. Karger AG, Basel
2004
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.