GENETIC FRONTIERS

BIO 102 General Botany - Constance Aurelle M. Ramirez A.Y. 2023-2024

Genetic Frontiers

  • Selective Breeding: Human intervention in breeding plants for desired traits.

  • Biotechnology: Use of organisms to create products that benefit humanity.

  • Genetic Engineering: Modification of an organism's DNA to produce new characteristics; involves manipulation of genes.

Recombinant DNA Technology

  • Recombinant DNA Technology: Techniques for combining genes from different organisms to create new DNA molecules.

  • Restriction Enzyme: Enzyme that cleaves DNA at specific base sequences for recombinant DNA applications.

Tools in Recombinant DNA Technology

  • Vector: Agent (like plasmids or viruses) used to transfer DNA between organisms.

  • Plasmid: Circular DNA molecule in bacteria that carries genes separately from the main DNA.

Constructing Recombinant DNA

  • Process:

    • DNA from two sources cut by the same restriction enzyme to create sticky ends.

    • Sticky ends form base pairs when mixed; ligase enzyme connects them to create recombinant DNA.

  • Outcome: Combination of bacterial plasmid and foreign DNA (e.g., from petunia).

Steps in Recombinant DNA Technology

  1. Cleaving the DNA: Plant DNA cut with restriction enzyme into fragments.

  2. Recombinant Plasmid Formation: Mixing plasmid and plant DNA to create recombinant plasmids; plasmids carry antibiotic resistance genes.

  3. Selection: Bacteria containing plasmids survive in antibiotic-containing medium.

Additional Concepts

  • Genetic Probe: Single-stranded nucleic acid that identifies complementary sequences.

  • DNA Cloning: Amplifying specific DNA sequences for structural and functional studies.

Agrobacterium tumefaciens Mechanism

  • Inserts its DNA into plant cells, leading to abnormal growth (tumors) by altering plant growth hormone production.

Steps to Produce Genetically Engineered Plants

  1. Insert foreign DNA into Agrobacterium tumefaciens.

  2. Transfer into cultured plant cells.

  3. Cultured cells develop into genetically engineered plants.

Determining DNA Sequence

  • DNA Sequencing: The method to ascertain nucleotide sequences in DNA.

  • Genome: Complete genetic information of an individual.

  • Genomics: Study of different organisms' genomes.

  • RNA Interference: Small RNA molecules that inhibit gene expression or RNA transcripts.

Applications of Genetic Engineering

  • Fields: Medicine, DNA fingerprinting, and agricultural biotechnology.

  • Forensic Analysis: Crime investigation and mass disaster victim identification.

  • Conservation: Studying endangered species and tracking food safety.

  • Transgenic Plants: Gaining importance in agriculture.