Introduction to Drosophila

Introduction to Drosophila

Other infor you can read: socmucimm, 2014

This notes from the Youtube video: Walter Jahn; GENETICS: Drosophila; 2020

Usual
USA/Upstream Activating Sequences

Videos: Lecture 5 Drosophila; UVUProfessor; 2015/02/09
Text Lecture: DEVELOPMENTAL BIOLOGY 3230; utah.edu

Why Drosophila

• Ideal for genetic studies
• Rapid life cycle
• Readiness to bread
• Polytene chromosomes
• Phenotypic mutatans

• Superficial Cleavage
  • Pull the egg surface down and to form cell membrane
  • Centrally located yolk confines cleavage to the cytoplasmic rim of the egg
• Syncytial blastoderm
  • All cleavage nuclei are contained within a common cytoplasm
• Cellular blastoderm
  • Each somatic nucleus is partitioned into a single cell

© Gerhard Scholtz, Carsten Wolff
Watters, Chris. (2005). Video Views and Reviews: Cytokinesis: A Phenomenon Overlooked Too Often. Cell biology education. 4. 10-8. 10.1187/cbe.04-08-0049.
© utah.edu
© Marc F Schetelig Carsten, et al.

Gastrulation

Reading Materials:

• Martin, Adam. (2020). The Physical Mechanisms of Drosophila Gastrulation: Mesoderm and Endoderm Invagination. Genetics. 214. 543-560. 10.1534/genetics.119.301292.

© Martin, Adam, et al.
© Dr. Brian E. Staveley
Fuse, Naoyuki & Yu, Fengwei & Hirose, Susumu. (2013). Gprk2 adjusts Fog signaling to organize cell movements in Drosophila gastrulation. Development (Cambridge, England). 140. 10.1242/dev.093625.

• Mid-blastula transition
  • Gastrulation begins
  • Slowdown of nuclear division
  • Increase in RNA transcription
• Ventral furrow
  • Invagination of prospective mesoderm
• Cephalic furrow
  • Separates procephalon from the germ band
• Germ band
  • Convergent extension

Anterior-Posterior Polarity

• Maternal effect genes
• Gap genes
• Pair-rule genes
• Segment polarity genes
• Homeotic selector genes

Development

Janardhan, P. & Hebert, M. & Ikeuchi, Katsushi. (1998). The space-time map applied to Drosophila embryogenesis. 144 - 153. 10.1109/BIA.1998.692429.
Ninova, Maria & Ronshaugen, Matthew & Griffiths-Jones, Sam. (2014). Conserved Temporal Patterns of MicroRNA Expression in Drosophila Support a Developmental Hourglass Model. Genome biology and evolution. 6. 10.1093/gbe/evu183.

• Oocyte develops and inside the ovary surrounded by support cells
• Nurse and follicle cells deposit maternal effect mRNA and proteins, and send signal essential for development to the Oocyte.
• After fertilization, the embryo establishes distinct regions based on expression patterns of maternal and zygotic genes.
• Segmentation and differentiation of the embryo corresponds to adult structures.

Maternal effect genes

• bicoid and Hunchback
  • Define anterior organizing center
• Nanos and Caudal
  • Define posterior organizing center
• Torso
  • Define terminal boundary region

A-P Pattern

Gene Expression patterns

Gap gene expression pattern

Inhibit each other by followed the hierarchy of them

• Pair-rule gene: fushi tarazu
• Segment Polarity genes: engrailed and wingless
• Segments and Parasegements
• Homeotic (Bub) Genes