alejandra manjarrez

Alejandra Manjarrez, PhD

Alejandra Manjarrez is a freelance science journalist who contributes to The Scientist. She has a PhD in systems biology from ETH Zurich and a master’s in molecular biology from Utrecht University. After years studying bacteria in a lab, she now spends most of her days reading, writing, and hunting science stories, either while traveling or visiting random libraries around the world. Her work has also appeared in Hakai, The Atlantic, and Lab Times.

Articles by Alejandra Manjarrez, PhD
Red and gray round cells floating on a red background. 
Low Intracellular Iron Levels May Keep Blood Stem Cells Young
Alejandra Manjarrez, PhD | Apr 8, 2024 | 3 min read
Removing excess iron from aging mouse blood-forming cells enhances their regenerative capacity.
A transverse section of stem wood from the researchers’ greenhouse-grown poplar tree.
CRISPR Trees Could Improve Paper Production
Alejandra Manjarrez, PhD | Aug 15, 2023 | 3 min read
Researchers edited several tree genes to improve suitability and sustainability in the pulp and paper industry.
Glass mosaic with the image of two people. The bodies are arbitrarily crossed by lines that divide them into amorphous fractions, some of them colored.
Noninherited Genetic Mutations Link to Schizophrenia
Alejandra Manjarrez, PhD | Jul 20, 2023 | 2 min read
By studying the genomes of more than 24,000 individuals, researchers discovered rare genetic mutations that may shed light on mechanisms underlying schizophrenia.
In this transgenic ant pupa surrounded by wild type pupae, green fluorescence on top reveals olfactory sensory neurons. On the bottom, the expression of red fluorescent protein shows throughout the ant pupa body.
Spying on Transgenic Ants Reveals How Their Brains Respond to Alarm Odors
Alejandra Manjarrez, PhD | Jul 7, 2023 | 2 min read
By successfully creating transgenic ants for the first time, researchers discovered that danger-signaling pheromones activate a sensory hub in the ants’ brains.
Microscopic image of a torn piece of gray plastic on a white background.
Alpine and Arctic Microbes Break Down Plastics
Alejandra Manjarrez, PhD | Jul 7, 2023 | 2 min read
Researchers identified cold-adapted microbes that degrade certain plastics at low temperatures, potentially saving energy in industrial recycling.
Brain cell in purple on a black background. Arc mRNAs are labeled green and are mainly localized in the cell nucleus and in the dendrites.
Short-lived Molecules Support Long-term Memory 
Alejandra Manjarrez, PhD | Jun 6, 2023 | 3 min read
A gene essential for information storage in the brain engages an autoregulatory feedback loop to consolidate memory.
Side and front view of a male human skull
Mechanical Force on the Skull May Aid Bone Regeneration
Alejandra Manjarrez, PhD | May 1, 2023 | 3 min read
By mechanically inducing the expansion of cranial sutures in young adult mice, researchers stimulated stem cell proliferation that is key to healing bone injuries.
Image of methylated DNA
Stress Increases Biological Age, But Recovery Can Revert It
Alejandra Manjarrez, PhD | Apr 21, 2023 | 2 min read
A new study relying on DNA methylation clocks suggests that the biological age of mouse and human cells can fluctuate in response to stressful events.
Bladder epithelial tissue, where cell junctions are shown in green and nuclei in blue. This was grown in vitro from cells taken from mice with chronic cystitis.
Bladder ‘Memory’ Influences Urinary Tract Infection Recurrence in Mice
Alejandra Manjarrez, PhD | Apr 12, 2023 | 3 min read
Urinary tract infections leave permanent epigenetic marks in the mouse bladder epithelium, reprogramming its response to subsequent infections, a study finds.
Image of the fly brain (grey) highlighting the population of neurons (pink) to which the gut-secreted peptide CCHa1 signals
A Protein-Rich Diet Helps Mice and Flies Sleep More Soundly: Study
Alejandra Manjarrez, PhD | Mar 24, 2023 | 3 min read
The effect appears to be mediated by a gut-secreted peptide that signals to neurons in the brain that modulate the response to mechanical vibrations.