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1. A Course-Based Research Experience: How Benefits Change with Increased Investment in Instructional Time

Author

Shaffer, Christopher D, Alvarez, Consuelo J, Bednarski, April E, Dunbar, David, Goodman, Anya L, Reinke, Catherine, Rosenwald, Anne G, Wolyniak, Michael J, Bailey, Cheryl, Barnard, Daron, Bazinet, Christopher, Beach, Dale L, Bedard, James EJ, Bhalla, Satish, Braverman, John, Burg, Martin, Chandrasekaran, Vidya, Chung, Hui-Min, Clase, Kari, DeJong, Randall J, DiAngelo, Justin R, Du, Chunguang, Eckdahl, Todd T, Eisler, Heather, Emerson, Julia A, Frary, Amy, Frohlich, Donald, Gosser, Yuying, Govind, Shubha, Haberman, Adam, Hark, Amy T, Hauser, Charles, Hoogewerf, Arlene, Hoopes, Laura LM, Howell, Carina E, Johnson, Diana, Jones, Christopher J, Kadlec, Lisa, Kaehler, Marian, Key, S Catherine Silver, Kleinschmit, Adam, Kokan, Nighat P, Kopp, Olga, Kuleck, Gary, Leatherman, Judith, Lopilato, Jane, MacKinnon, Christy, Martinez-Cruzado, Juan Carlos, McNeil, Gerard, Mel, Stephanie, Mistry, Hemlata, Nagengast, Alexis, Overvoorde, Paul, Paetkau, Don W, Parrish, Susan, Peterson, Celeste N, Preuss, Mary, Reed, Laura K, Revie, Dennis, Robic, Srebrenka, Roecklein-Canfield, Jennifer, Rubin, Michael R, Saville, Kenneth, Schroeder, Stephanie, Sharif, Karim, Shaw, Mary, Skuse, Gary, Smith, Christopher D, Smith, Mary A, Smith, Sheryl T, Spana, Eric, Spratt, Mary, Sreenivasan, Aparna, Stamm, Joyce, Szauter, Paul, Thompson, Jeffrey S, Wawersik, Matthew, Youngblom, James, Zhou, Leming, Mardis, Elaine R, Buhler, Jeremy, Leung, Wilson, Lopatto, David, and Elgin, Sarah CR

Subjects
Attitude, Biology, Cooperative Behavior, Curriculum, Data Collection, Faculty, Genome, Genomics, Humans, Knowledge, Learning, Molecular Sequence Annotation, Program Evaluation, Research, Research Personnel, Self Report, Surveys and Questionnaires, Time Factors, Curriculum and Pedagogy, Education
Abstract

There is widespread agreement that science, technology, engineering, and mathematics programs should provide undergraduates with research experience. Practical issues and limited resources, however, make this a challenge. We have developed a bioinformatics project that provides a course-based research experience for students at a diverse group of schools and offers the opportunity to tailor this experience to local curriculum and institution-specific student needs. We assessed both attitude and knowledge gains, looking for insights into how students respond given this wide range of curricular and institutional variables. While different approaches all appear to result in learning gains, we find that a significant investment of course time is required to enable students to show gains commensurate to a summer research experience. An alumni survey revealed that time spent on a research project is also a significant factor in the value former students assign to the experience one or more years later. We conclude: 1) implementation of a bioinformatics project within the biology curriculum provides a mechanism for successfully engaging large numbers of students in undergraduate research; 2) benefits to students are achievable at a wide variety of academic institutions; and 3) successful implementation of course-based research experiences requires significant investment of instructional time for students to gain full benefit.

Published
2014

2. A Course-Based Research Experience: How Benefits Change with Increased Investment in Instructional Time

Author

Shaffer, Christopher D., Alvarez, Consuelo J., Bednarski, April E., Dunbar, David, Goodman, Anya L., Reinke, Catherine, Rosenwald, Anne G., Wolyniak, Michael J., Bailey, Cheryl, Barnard, Daron, Bazinet, Christopher, Beach, Dale L., Bedard, James E. J., Bhalla, Satish, Braverman, John, Burg, Martin, Chandrasekaran, Vidya, Chung, Hui-Min, Clase, Kari, DeJong, Randall J., DiAngelo, Justin R., Du, Chunguang, Eckdahl, Todd T., Eisler, Heather, Emerson, Julia A., Frary, Amy, Frohlich, Donald, Gosser, Yuying, Govind, Shubha, Haberman, Adam, Hark, Amy T., Hauser, Charles, Hoogewerf, Arlene, Hoopes, Laura L. M., Howell, Carina E., Johnson, Diana, Jones, Christopher J., Kadlec, Lisa, Kaehler, Marian, Key, S. Catherine Silver, Kleinschmit, Adam, Kokan, Nighat P., Kopp, Olga, Kuleck, Gary, Leatherman, Judith, Lopilato, Jane, MacKinnon, Christy, Martinez-Cruzado, Juan Carlos, McNeil, Gerard, Mel, Stephanie, Mistry, Hemlata, Nagengast, Alexis, Overvoorde, Paul, Paetkau, Don W., Parrish, Susan, Peterson, Celeste N., Preuss, Mary, Reed, Laura K., Revie, Dennis, Robic, Srebrenka, Roecklein-Canfield, Jennifer, Rubin, Michael R., Saville, Kenneth, Schroeder, Stephanie, Sharif, Karim, Shaw, Mary, Skuse, Gary, Smith, Christopher D., Smith, Mary A., Smith, Sheryl T., Spana, Eric, Spratt, Mary, Sreenivasan, Aparna, Stamm, Joyce, Szauter, Paul, Thompson, Jeffrey S., Wawersik, Matthew, Youngblom, James, Zhou, Leming, Mardis, Elaine R., Buhler, Jeremy, Leung, Wilson, Lopatto, David, and Elgin, Sarah C. R.

Abstract

There is widespread agreement that science, technology, engineering, and mathematics programs should provide undergraduates with research experience. Practical issues and limited resources, however, make this a challenge. We have developed a bioinformatics project that provides a course-based research experience for students at a diverse group of schools and offers the opportunity to tailor this experience to local curriculum and institution-specific student needs. We assessed both attitude and knowledge gains, looking for insights into how students respond given this wide range of curricular and institutional variables. While different approaches all appear to result in learning gains, we find that a significant investment of course time is required to enable students to show gains commensurate to a summer research experience. An alumni survey revealed that time spent on a research project is also a significant factor in the value former students assign to the experience one or more years later. We conclude: 1) implementation of a bioinformatics project within the biology curriculum provides a mechanism for successfully engaging large numbers of students in undergraduate research; 2) benefits to students are achievable at a wide variety of academic institutions; and 3) successful implementation of course-based research experiences requires significant investment of instructional time for students to gain full benefit. [Contains 82 pages of Supplemental Material, which can be found at: http://www.lifescied.org/content/suppl/2014/02/12/13.1.111.DC1.html.]

Published
2014
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3. Endosymbiotic origins of sex

Author

Bazinet, Christopher

Subjects
Sex -- History, Sex -- Research, Endosymbiosis -- Research, Biological sciences
Abstract

An endosymbiotic model for the evolutionary origins of sex is described. The hypothesis regarding the descend of contemporary life cycle of germline cells from the lifecycle of the endosymbiotic ancestor of the mitochondrian is tested.

Published
2004

4. Facilitating Growth through Frustration: Using Genomics Research in a Course-Based Undergraduate Research Experience

Author

Lopatto, David, primary, Rosenwald, Anne G., additional, DiAngelo, Justin R., additional, Hark, Amy T., additional, Skerritt, Matthew, additional, Wawersik, Matthew, additional, Allen, Anna K., additional, Alvarez, Consuelo, additional, Anderson, Sara, additional, Arrigo, Cindy, additional, Arsham, Andrew, additional, Barnard, Daron, additional, Bazinet, Christopher, additional, Bedard, James E. J., additional, Bose, Indrani, additional, Braverman, John M., additional, Burg, Martin G., additional, Burgess, Rebecca C., additional, Croonquist, Paula, additional, Du, Chunguang, additional, Dubowsky, Sondra, additional, Eisler, Heather, additional, Escobar, Matthew A., additional, Foulk, Michael, additional, Furbee, Emily, additional, Giarla, Thomas, additional, Glaser, Rivka L., additional, Goodman, Anya L., additional, Gosser, Yuying, additional, Haberman, Adam, additional, Hauser, Charles, additional, Hays, Shan, additional, Howell, Carina E., additional, Jemc, Jennifer, additional, Johnson, M. Logan, additional, Jones, Christopher J., additional, Kadlec, Lisa, additional, Kagey, Jacob D., additional, Keller, Kimberly L., additional, Kennell, Jennifer, additional, Key, S. Catherine Silver, additional, Kleinschmit, Adam J., additional, Kleinschmit, Melissa, additional, Kokan, Nighat P., additional, Kopp, Olga Ruiz, additional, Laakso, Meg M., additional, Leatherman, Judith, additional, Long, Lindsey J., additional, Manier, Mollie, additional, Martinez-Cruzado, Juan C., additional, Matos, Luis F., additional, McClellan, Amie Jo, additional, McNeil, Gerard, additional, Merkhofer, Evan, additional, Mingo, Vida, additional, Mistry, Hemlata, additional, Mitchell, Elizabeth, additional, Mortimer, Nathan T., additional, Mukhopadhyay, Debaditya, additional, Myka, Jennifer Leigh, additional, Nagengast, Alexis, additional, Overvoorde, Paul, additional, Paetkau, Don, additional, Paliulis, Leocadia, additional, Parrish, Susan, additional, Preuss, Mary Lai, additional, Price, James V., additional, Pullen, Nicholas A., additional, Reinke, Catherine, additional, Revie, Dennis, additional, Robic, Srebrenka, additional, Roecklein-Canfield, Jennifer A., additional, Rubin, Michael R., additional, Sadikot, Takrima, additional, Sanford, Jamie Siders, additional, Santisteban, Maria, additional, Saville, Kenneth, additional, Schroeder, Stephanie, additional, Shaffer, Christopher D., additional, Sharif, Karim A., additional, Sklensky, Diane E., additional, Small, Chiyedza, additional, Smith, Mary, additional, Smith, Sheryl, additional, Spokony, Rebecca, additional, Sreenivasan, Aparna, additional, Stamm, Joyce, additional, Sterne-Marr, Rachel, additional, Teeter, Katherine C., additional, Thackeray, Justin, additional, Thompson, Jeffrey S., additional, Peters, Stephanie Toering, additional, Van Stry, Melanie, additional, Velazquez-Ulloa, Norma, additional, Wolfe, Cindy, additional, Youngblom, James, additional, Yowler, Brian, additional, Zhou, Leming, additional, Brennan, Janie, additional, Buhler, Jeremy, additional, Leung, Wilson, additional, Reed, Laura K., additional, and Elgin, Sarah C. R., additional

Published
2020
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5. The Drosophila clathrin heavy chain gene: clathrin function is essential in a mutlicellular organism

Author

Bazinet, Christopher, Katzen, Alisa L., Morgan, Margaret, Mahowald, Anthony P., and Lemmon, Sandra K.

Subjects
Clathrin -- Influence, Drosophila -- Analysis, Polymerase chain reaction -- Usage, Spermatogenesis -- Analysis, Biological sciences
Abstract

The role of clathrin in cellular morphogenesis and developmental signal transduction was analyzed using a genetic approach. The clathrin heavy chain (HC) is a vital structural polypeptide of the cytoplasmic surface lattice of clathrin-coated pits and vesicles. The experiment isolated the gene of the Drosophila melanogaster using several molecular and classical genetic approaches. A tiny particle of the HC gene was magnified using a polymerase chain reaction which employed degenerate primers based on mammalian and yeast clathrin HC sequences. Thus, it has been proved that clathrin can be used in spermatogenesis.

Published
1993

6. Retrotransposons Are the Major Contributors to the Expansion of theDrosophila ananassaeMuller F Element

Author

Leung, Wilson, primary, Shaffer, Christopher D, additional, Chen, Elizabeth J, additional, Quisenberry, Thomas J, additional, Ko, Kevin, additional, Braverman, John M, additional, Giarla, Thomas C, additional, Mortimer, Nathan T, additional, Reed, Laura K, additional, Smith, Sheryl T, additional, Robic, Srebrenka, additional, McCartha, Shannon R, additional, Perry, Danielle R, additional, Prescod, Lindsay M, additional, Sheppard, Zenyth A, additional, Saville, Ken J, additional, McClish, Allison, additional, Morlock, Emily A, additional, Sochor, Victoria R, additional, Stanton, Brittney, additional, Veysey-White, Isaac C, additional, Revie, Dennis, additional, Jimenez, Luis A, additional, Palomino, Jennifer J, additional, Patao, Melissa D, additional, Patao, Shane M, additional, Himelblau, Edward T, additional, Campbell, Jaclyn D, additional, Hertz, Alexandra L, additional, McEvilly, Maddison F, additional, Wagner, Allison R, additional, Youngblom, James, additional, Bedi, Baljit, additional, Bettincourt, Jeffery, additional, Duso, Erin, additional, Her, Maiye, additional, Hilton, William, additional, House, Samantha, additional, Karimi, Masud, additional, Kumimoto, Kevin, additional, Lee, Rebekah, additional, Lopez, Darryl, additional, Odisho, George, additional, Prasad, Ricky, additional, Robbins, Holly Lyn, additional, Sandhu, Tanveer, additional, Selfridge, Tracy, additional, Tsukashima, Kara, additional, Yosif, Hani, additional, Kokan, Nighat P, additional, Britt, Latia, additional, Zoellner, Alycia, additional, Spana, Eric P, additional, Chlebina, Ben T, additional, Chong, Insun, additional, Friedman, Harrison, additional, Mammo, Danny A, additional, Ng, Chun L, additional, Nikam, Vinayak S, additional, Schwartz, Nicholas U, additional, Xu, Thomas Q, additional, Burg, Martin G, additional, Batten, Spencer M, additional, Corbeill, Lindsay M, additional, Enoch, Erica, additional, Ensign, Jesse J, additional, Franks, Mary E, additional, Haiker, Breanna, additional, Ingles, Judith A, additional, Kirkland, Lyndsay D, additional, Lorenz-Guertin, Joshua M, additional, Matthews, Jordan, additional, Mittig, Cody M, additional, Monsma, Nicholaus, additional, Olson, Katherine J, additional, Perez-Aragon, Guillermo, additional, Ramic, Alen, additional, Ramirez, Jordan R, additional, Scheiber, Christopher, additional, Schneider, Patrick A, additional, Schultz, Devon E, additional, Simon, Matthew, additional, Spencer, Eric, additional, Wernette, Adam C, additional, Wykle, Maxine E, additional, Zavala-Arellano, Elizabeth, additional, McDonald, Mitchell J, additional, Ostby, Kristine, additional, Wendland, Peter, additional, DiAngelo, Justin R, additional, Ceasrine, Alexis M, additional, Cox, Amanda H, additional, Docherty, James E B, additional, Gingras, Robert M, additional, Grieb, Stephanie M, additional, Pavia, Michael J, additional, Personius, Casey L, additional, Polak, Grzegorz L, additional, Beach, Dale L, additional, Cerritos, Heaven L, additional, Horansky, Edward A, additional, Sharif, Karim A, additional, Moran, Ryan, additional, Parrish, Susan, additional, Bickford, Kirsten, additional, Bland, Jennifer, additional, Broussard, Juliana, additional, Campbell, Kerry, additional, Deibel, Katelynn E, additional, Forka, Richard, additional, Lemke, Monika C, additional, Nelson, Marlee B, additional, O'Keeffe, Catherine, additional, Ramey, S Mariel, additional, Schmidt, Luke, additional, Villegas, Paola, additional, Jones, Christopher J, additional, Christ, Stephanie L, additional, Mamari, Sami, additional, Rinaldi, Adam S, additional, Stity, Ghazal, additional, Hark, Amy T, additional, Scheuerman, Mark, additional, Silver Key, S Catherine, additional, McRae, Briana D, additional, Haberman, Adam S, additional, Asinof, Sam, additional, Carrington, Harriette, additional, Drumm, Kelly, additional, Embry, Terrance, additional, McGuire, Richard, additional, Miller-Foreman, Drew, additional, Rosen, Stella, additional, Safa, Nadia, additional, Schultz, Darrin, additional, Segal, Matt, additional, Shevin, Yakov, additional, Svoronos, Petros, additional, Vuong, Tam, additional, Skuse, Gary, additional, Paetkau, Don W, additional, Bridgman, Rachael K, additional, Brown, Charlotte M, additional, Carroll, Alicia R, additional, Gifford, Francesca M, additional, Gillespie, Julie Beth, additional, Herman, Susan E, additional, Holtcamp, Krystal L, additional, Host, Misha A, additional, Hussey, Gabrielle, additional, Kramer, Danielle M, additional, Lawrence, Joan Q, additional, Martin, Madeline M, additional, Niemiec, Ellen N, additional, O'Reilly, Ashleigh P, additional, Pahl, Olivia A, additional, Quintana, Guadalupe, additional, Rettie, Elizabeth A S, additional, Richardson, Torie L, additional, Rodriguez, Arianne E, additional, Rodriguez, Mona O, additional, Schiraldi, Laura, additional, Smith, Joanna J, additional, Sugrue, Kelsey F, additional, Suriano, Lindsey J, additional, Takach, Kaitlyn E, additional, Vasquez, Arielle M, additional, Velez, Ximena, additional, Villafuerte, Elizabeth J, additional, Vives, Laura T, additional, Zellmer, Victoria R, additional, Hauke, Jeanette, additional, Hauser, Charles R, additional, Barker, Karolyn, additional, Cannon, Laurie, additional, Parsamian, Perouza, additional, Parsons, Samantha, additional, Wichman, Zachariah, additional, Bazinet, Christopher W, additional, Johnson, Diana E, additional, Bangura, Abubakarr, additional, Black, Jordan A, additional, Chevee, Victoria, additional, Einsteen, Sarah A, additional, Hilton, Sarah K, additional, Kollmer, Max, additional, Nadendla, Rahul, additional, Stamm, Joyce, additional, Fafara-Thompson, Antoinette E, additional, Gygi, Amber M, additional, Ogawa, Emmy E, additional, Van Camp, Matt, additional, Kocsisova, Zuzana, additional, Leatherman, Judith L, additional, Modahl, Cassie M, additional, Rubin, Michael R, additional, Apiz-Saab, Susana S, additional, Arias-Mejias, Suzette M, additional, Carrion-Ortiz, Carlos F, additional, Claudio-Vazquez, Patricia N, additional, Espada-Green, Debbie M, additional, Feliciano-Camacho, Marium, additional, Gonzalez-Bonilla, Karina M, additional, Taboas-Arroyo, Mariela, additional, Vargas-Franco, Dorianmarie, additional, Montañez-Gonzalez, Raquel, additional, Perez-Otero, Joseph, additional, Rivera-Burgos, Myrielis, additional, Rivera-Rosario, Francisco J, additional, Eisler, Heather L, additional, Alexander, Jackie, additional, Begley, Samatha K, additional, Gabbard, Deana, additional, Allen, Robert J, additional, Aung, Wint Yan, additional, Barshop, William D, additional, Boozalis, Amanda, additional, Chu, Vanessa P, additional, Davis, Jeremy S, additional, Duggal, Ryan N, additional, Franklin, Robert, additional, Gavinski, Katherine, additional, Gebreyesus, Heran, additional, Gong, Henry Z, additional, Greenstein, Rachel A, additional, Guo, Averill D, additional, Hanson, Casey, additional, Homa, Kaitlin E, additional, Hsu, Simon C, additional, Huang, Yi, additional, Huo, Lucy, additional, Jacobs, Sarah, additional, Jia, Sasha, additional, Jung, Kyle L, additional, Wai-Chee Kong, Sarah, additional, Kroll, Matthew R, additional, Lee, Brandon M, additional, Lee, Paul F, additional, Levine, Kevin M, additional, Li, Amy S, additional, Liu, Chengyu, additional, Liu, Max Mian, additional, Lousararian, Adam P, additional, Lowery, Peter B, additional, Mallya, Allyson P, additional, Marcus, Joseph E, additional, Ng, Patrick C, additional, Nguyen, Hien P, additional, Patel, Ruchik, additional, Precht, Hashini, additional, Rastogi, Suchita, additional, Sarezky, Jonathan M, additional, Schefkind, Adam, additional, Schultz, Michael B, additional, Shen, Delia, additional, Skorupa, Tara, additional, Spies, Nicholas C, additional, Stancu, Gabriel, additional, Vivian Tsang, Hiu Man, additional, Turski, Alice L, additional, Venkat, Rohit, additional, Waldman, Leah E, additional, Wang, Kaidi, additional, Wang, Tracy, additional, Wei, Jeffrey W, additional, Wu, Dennis Y, additional, Xiong, David D, additional, Yu, Jack, additional, Zhou, Karen, additional, McNeil, Gerard P, additional, Fernandez, Robert W, additional, Menzies, Patrick Gomez, additional, Gu, Tingting, additional, Buhler, Jeremy, additional, Mardis, Elaine R, additional, and Elgin, Sarah C R, additional

Published
2017
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14. Neurotransmitter Transporter-Like: A Male Germlinespecific SLC6 Transporter Required for Drosophila Spermiogenesis.

Author

Chatterjee, Nabanita, Rollins, Janet, Mahowald, Anthony P., and Bazinet, Christopher

Subjects
GLYCINE, AMINO acid neurotransmitters, ACETIC acid, TUBULINS, FRUIT flies, EMBRYOLOGY, SEMINAL vesicles, GERM cells, GENOTYPE-environment interaction, MOBILE genetic elements
Abstract

The SLC6 class of membrane transporters, known primarily as neurotransmitter transporters, is increasingly appreciated for its roles in nutritional uptake of amino acids and other developmentally specific functions. A Drosophila SLC6 gene, Neurotransmitter transporter-like (Ntl), is expressed only in the male germline. Mobilization of a transposon inserted near the 3' end of the Ntl coding region yields male-sterile mutants defining a single complementation group. Germline transformation with Ntl cDNAs under control of male germline-specific control elements restores Ntl/Ntl homozygotes to normal fertility, indicating that Ntl is required only in the germ cells. In mutant males, sperm morphogenesis appears normal, with elongated, individualized and coiled spermiogenic cysts accumulating at the base of the testes. However, no sperm are transferred to the seminal vesicle. The level of polyglycylation of Ntl mutant sperm tubulin appears to be significantly lower than that of wild type controls. Glycine transporters are the most closely related SLC6 transporters to Ntl, suggesting that Ntl functions as a glycine transporter in developing sperm, where augmentation of the cytosolic pool of glycine may be required for the polyglycylation of the massive amounts of tubulin in the fly's giant sperm. The male-sterile phenotype of Ntl mutants may provide a powerful genetic system for studying the function of an SLC6 transporter family in a model organism. [ABSTRACT FROM AUTHOR]

Published
2011
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16. Genetic dissection of sperm individualization in Drosophila melanogaster

Author

Fabrizio, James J., Hime, Gary, Lemmon, Sandra K., and Bazinet, Christopher

Abstract

The morphogenesis of spermatids generally takes place within a syncytium, in which all spermatid nuclei descended from a primary spermatocyte remain connected via an extensive network of cytoplasmic bridges. A late step in sperm maturation therefore requires the physical resolution of the syncytium, or cyst, into individual cells, a process sometimes referred to as sperm individualization. Despite the identification of specialized machinery involved in the individualization of Drosophila spermatids (Tokuyasu, K. T., Peacock, W. J. and Hardy, R. W. (1972) Z. Zellforsch 124, 479-506), and of many Drosophila genes mutable to male-sterile phenotypes, little is known of the mechanisms by which this extensive remodeling of the cyst is accomplished. Here, the identification of a major cytoskeletal component of the individualization complex as actin is confirmed with a simple fluorescence assay. Using rhodamine-phalloidin as a probe, the individualization complex is readily visualized forming around bundles of spermatid nuclei at one end of highly elongated cysts, then translocating along the length of the cysts. The structure of the individualization complex in a male-sterile clathrin heavy chain (Chc) mutant is observed to be reduced or disrupted relative to wild-type, consistent with the individualization-deficient phenotype of this mutant. Using the fluorescence assay, a sampling of male-sterile mutant phenotypes in which spermatogenesis proceeds to the assembly of highly elongated cysts distinguishes at least four different phenotypic classes: (1) mutations (nanking class) that block or significantly retard the assembly of the actin-based individualization complex around the nuclear bundle, (2) mutations (dud class) in which the individualization complex assembles in/around the nuclear bundle, but fails to translocate down the cyst, (3) mutations (mulet class) that allow the assembly of a morphologically normal individualization complex around the nuclear bundle, but result in a breakdown in the complex after it begins to translocate down the cyst, and (4) mutations (purity of essence class) that allow the assembly of a motile but morphologically altered or reduced individualization complex. Individualization also fails in a number of mutants with altered nuclear shape, consistent with the hypothesis that spermatid nuclei provide a physical scaffolding for the assembly of the individualization complex. Genetic analysis suggests that a substantial number of additional loci with phenotypes distinguishable with this assay remain to be identified. The large proportion of male-sterile mutations resulting in a late block to spermatogenesis, in which highly elongated cysts fail to be individualized, suggest a substantial susceptibility of this process to a broad range of cellular perturbations. The massive reorganization of cyst cytoplasm required at individualization is expected to be a correspondingly complex function requiring exquisite coordination of multiple cytoplasmic functions, and may account for the previously noted high frequency with which Drosophila genes are mutable to male-sterile phenotypes.

Published
1998
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21. Depletion of plasma membrane PtdIns(4,5)P2 reveals essential roles for phosphoinositides in flagellar biogenesis.

Author

Ho-Chun Wei, Rollins, Janet, Fabian, Lacramioara, Hayes, Madeline, Polevoy, Gordon, Bazinet, Christopher, and Brill, Julie A.

Subjects
CELL membrane formation, MICROTUBULES, PHOSPHOINOSITIDES, FLAGELLA (Microbiology), DROSOPHILA melanogaster, SPERMIOGENESIS in animals
Abstract

Axonemes are microtubule-based organelles of crucial importance in the structure and function of eukaryotic cilia and flagella. Despite great progress in understanding how axonemes are assembled, the signals that initiate axoneme outgrowth remain unknown. Here, we identified phosphatidylinositol phosphates (phosphoinositides) as key regulators of early stages of axoneme outgrowth in Drosophila melanogaster spermatogenesis. In a study of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] function in developing Drosophila male germ cells, we depleted PtdIns(4,5)P2 by expression of a potent phosphoinositide phosphatase. Phosphatase expression dramatically inhibited sperm tail formation and perturbed microtubule organization in a manner reversible by co-expression of a PtdIns 4-phosphate 5-kinase. Depletion of PtdIns(4,5)P2 caused increased levels of basal body γ-tubulin and altered the distribution of proteins known to be required for axoneme assembly. Examination of PtdIns(4,5)P2-depleted spermatids by transmission electron microscopy revealed defects in basal body docking to the nuclear envelope, and in axoneme architecture and integrity of the developing flagellar axoneme and axial sheath. Our results provide the first evidence that phosphoinositides act at several steps during flagellar biogenesis, coordinately regulating microtubule and membrane organization. They further suggest that phosphoinositides play evolutionarily conserved roles in flagella and cilia, across phyla and in structurally diverse cell types. [ABSTRACT FROM AUTHOR]

Published
2008

22. Tubulin-binding cofactor E-like (TBCEL), the protein product of the mulet gene, is required in the germline for the regulation of inter-flagellar microtubule dynamics during spermatid individualization.

Author

Fabrizio JJ, Rollins J, Bazinet CW, Wegener S, Koziy I, Daniel R, Lombardo V, Pryce D, Bharrat K, Innabi E, Villanobos M, Mendoza G, Ferrara E, Rodway S, Vicioso M, Siracusa V, Dailey E, Pronovost J, Innabi S, Patel V, DeSouza N, Quaranto D, and Niknejad A

Subjects
Animals, Drosophila, Fluorescent Antibody Technique, Gene Expression Regulation, Gene Knockdown Techniques, Germ Cells cytology, Male, Mutation, Phenotype, Spermatids cytology, Spermatids ultrastructure, Testis cytology, Testis metabolism, Drosophila Proteins genetics, Germ Cells metabolism, Molecular Chaperones genetics, Spermatids metabolism, Spermatogenesis genetics
Abstract

Individual sperm cells are resolved from a syncytium during late step of spermiogenesis known as individualization, which is accomplished by an Individualization Complex (IC) composed of 64 investment cones. mulet encodes Tubulin-binding cofactor E-like (TBCEL), suggesting a role for microtubule dynamics in individualization. Indeed, a population of ∼100 cytoplasmic microtubules fails to disappear in mulet mutant testes during spermatogenesis. This persistence, detected using epi-fluorescence and electron microscopy, suggests that removal of these microtubules by TBCEL is a prerequisite for individualization. Immunofluorescence reveals TBCEL expression in elongated spermatid cysts. In addition, testes from mulet mutant males were rescued to wild type using tubulin-Gal4 to drive TBCEL expression, indicating that the mutant phenotype is caused by the lack of TBCEL. Finally, RNAi driven by bam -GAL4 successfully phenocopied mulet , confirming that mulet is required in the germline for individualization. We propose a model in which the cytoplasmic microtubules serve as alternate tracks for investment cones in mulet mutant testes.This article has an associated First Person interview with the first author of the paper., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

Published
2020
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23. Retrotransposons Are the Major Contributors to the Expansion of the Drosophila ananassae Muller F Element.

Author

Leung W, Shaffer CD, Chen EJ, Quisenberry TJ, Ko K, Braverman JM, Giarla TC, Mortimer NT, Reed LK, Smith ST, Robic S, McCartha SR, Perry DR, Prescod LM, Sheppard ZA, Saville KJ, McClish A, Morlock EA, Sochor VR, Stanton B, Veysey-White IC, Revie D, Jimenez LA, Palomino JJ, Patao MD, Patao SM, Himelblau ET, Campbell JD, Hertz AL, McEvilly MF, Wagner AR, Youngblom J, Bedi B, Bettincourt J, Duso E, Her M, Hilton W, House S, Karimi M, Kumimoto K, Lee R, Lopez D, Odisho G, Prasad R, Robbins HL, Sandhu T, Selfridge T, Tsukashima K, Yosif H, Kokan NP, Britt L, Zoellner A, Spana EP, Chlebina BT, Chong I, Friedman H, Mammo DA, Ng CL, Nikam VS, Schwartz NU, Xu TQ, Burg MG, Batten SM, Corbeill LM, Enoch E, Ensign JJ, Franks ME, Haiker B, Ingles JA, Kirkland LD, Lorenz-Guertin JM, Matthews J, Mittig CM, Monsma N, Olson KJ, Perez-Aragon G, Ramic A, Ramirez JR, Scheiber C, Schneider PA, Schultz DE, Simon M, Spencer E, Wernette AC, Wykle ME, Zavala-Arellano E, McDonald MJ, Ostby K, Wendland P, DiAngelo JR, Ceasrine AM, Cox AH, Docherty JEB, Gingras RM, Grieb SM, Pavia MJ, Personius CL, Polak GL, Beach DL, Cerritos HL, Horansky EA, Sharif KA, Moran R, Parrish S, Bickford K, Bland J, Broussard J, Campbell K, Deibel KE, Forka R, Lemke MC, Nelson MB, O'Keeffe C, Ramey SM, Schmidt L, Villegas P, Jones CJ, Christ SL, Mamari S, Rinaldi AS, Stity G, Hark AT, Scheuerman M, Silver Key SC, McRae BD, Haberman AS, Asinof S, Carrington H, Drumm K, Embry T, McGuire R, Miller-Foreman D, Rosen S, Safa N, Schultz D, Segal M, Shevin Y, Svoronos P, Vuong T, Skuse G, Paetkau DW, Bridgman RK, Brown CM, Carroll AR, Gifford FM, Gillespie JB, Herman SE, Holtcamp KL, Host MA, Hussey G, Kramer DM, Lawrence JQ, Martin MM, Niemiec EN, O'Reilly AP, Pahl OA, Quintana G, Rettie EAS, Richardson TL, Rodriguez AE, Rodriguez MO, Schiraldi L, Smith JJ, Sugrue KF, Suriano LJ, Takach KE, Vasquez AM, Velez X, Villafuerte EJ, Vives LT, Zellmer VR, Hauke J, Hauser CR, Barker K, Cannon L, Parsamian P, Parsons S, Wichman Z, Bazinet CW, Johnson DE, Bangura A, Black JA, Chevee V, Einsteen SA, Hilton SK, Kollmer M, Nadendla R, Stamm J, Fafara-Thompson AE, Gygi AM, Ogawa EE, Van Camp M, Kocsisova Z, Leatherman JL, Modahl CM, Rubin MR, Apiz-Saab SS, Arias-Mejias SM, Carrion-Ortiz CF, Claudio-Vazquez PN, Espada-Green DM, Feliciano-Camacho M, Gonzalez-Bonilla KM, Taboas-Arroyo M, Vargas-Franco D, Montañez-Gonzalez R, Perez-Otero J, Rivera-Burgos M, Rivera-Rosario FJ, Eisler HL, Alexander J, Begley SK, Gabbard D, Allen RJ, Aung WY, Barshop WD, Boozalis A, Chu VP, Davis JS, Duggal RN, Franklin R, Gavinski K, Gebreyesus H, Gong HZ, Greenstein RA, Guo AD, Hanson C, Homa KE, Hsu SC, Huang Y, Huo L, Jacobs S, Jia S, Jung KL, Wai-Chee Kong S, Kroll MR, Lee BM, Lee PF, Levine KM, Li AS, Liu C, Liu MM, Lousararian AP, Lowery PB, Mallya AP, Marcus JE, Ng PC, Nguyen HP, Patel R, Precht H, Rastogi S, Sarezky JM, Schefkind A, Schultz MB, Shen D, Skorupa T, Spies NC, Stancu G, Vivian Tsang HM, Turski AL, Venkat R, Waldman LE, Wang K, Wang T, Wei JW, Wu DY, Xiong DD, Yu J, Zhou K, McNeil GP, Fernandez RW, Menzies PG, Gu T, Buhler J, Mardis ER, and Elgin SCR

Subjects
Animals, Base Composition genetics, Base Sequence, Codon genetics, Female, Gene Expression Profiling, Genes, Insect, Histones metabolism, Protein Processing, Post-Translational genetics, Wolbachia genetics, Chromosomes genetics, Drosophila genetics, Retroelements genetics
Abstract

The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster , but it is substantially larger (>18.7 Mb) in D. ananassae To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes ( e.g. , larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae Compared to D. melanogaster , the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5' ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains., (Copyright © 2017 Leung et al.)

Published
2017
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