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John Lovell

@jotlovell

Helping to make genomics useful for crop improvement, ecology, evolutionary biology, and conservation HudsonAlpha Genome Sequencing Center and DOE Joint Genome Institute

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12.09.2023
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Latest posts by John Lovell @jotlovell

There are a bunch of ways ... here is one:
```
ggplot()+ggtitle(expression(paste("Reference: ", italic("Quercus rubra"), " is the best")))
```

05.03.2026 17:59 πŸ‘ 2 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

I'm super excited to share that this article was published today in Science! www.science.org/doi/10.1126/...

All made possible by the fantastic group of donors, volunteers and scientists at The American Chestnut Foundation (tacf.org), HudsonAlpha Institute for Biotechnology, and our collaborators.

12.02.2026 19:26 πŸ‘ 100 πŸ” 45 πŸ’¬ 3 πŸ“Œ 5
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Pan-genomes Meeting - 2026 Population, Evolutionary, and Quantitative Genetics Conference Visit our website to learn more.

We’re excited to share the Pan-genomes Doorstep Meeting @ #PEQG26! Join this 3-hour workshop on evolutionary applications of pangenomics, covering construction, analysis, phylogenetics, annotation & graph QC. Register separately or as an add-on to PEQG: genetics-gsa.org/peqg-2026/do...

06.02.2026 18:03 πŸ‘ 9 πŸ” 9 πŸ’¬ 0 πŸ“Œ 0

This week in @science.org, a celebration of plant pangenomes. A pangenome analysis for massively polyploid sugarcane species, and one for Brassica rapa giving insight into subspeciation.

What's all the fuss about pangenomes? Pamela and Douglas Soltis explore this in an insightful Perspective(1/4)

06.02.2026 09:57 πŸ‘ 31 πŸ” 17 πŸ’¬ 1 πŸ“Œ 0

We added this analysis to the published version (table 1). Short answer, it solves some problem, but creates others!

02.02.2026 21:52 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Thanks again to @tomasbruna.bsky.social and @jgi.doe.gov for making this work possible!

30.01.2026 12:41 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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Second, we re-annotated all the genomes with the popular ML tool, Helixer. Helixer solves some PAV methodological artifacts, but it also produces implausible gene models at a high rate.

For example, 1 in 5 Helixer gene models have non-canonical splice sites or very short internal introns/exons.

30.01.2026 12:41 πŸ‘ 2 πŸ” 0 πŸ’¬ 2 πŸ“Œ 0

This article is now published! academic.oup.com/nargab/artic...
We’ve added a few new analyses. First off, we show that, while gene presence absence variation (PAV) scales with evolutionary distance in both plants and animals, the base level and rate of accrual are both twice as high in plants.

30.01.2026 12:41 πŸ‘ 23 πŸ” 17 πŸ’¬ 2 πŸ“Œ 0
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I am excited to offer a postdoctoral research position in my lab in Oxford studying the distribution of small RNAs during plant sexual reproduction. shorturl.at/7Goxt
Reposts appreciated!
Obligatory cat video to brighten your day. :-)

26.01.2026 16:31 πŸ‘ 157 πŸ” 88 πŸ’¬ 4 πŸ“Œ 5

@amarques.bsky.social really knows how to tell a story graphically. Maybe the most information dense but visually appealing figure I've seen recently!

21.01.2026 17:54 πŸ‘ 6 πŸ” 2 πŸ’¬ 1 πŸ“Œ 0
Phytozome Tools for exploring the Phytozome collection of green plant genomes

This work would not have been possible without Jill M. Farrant, @jleebensmack.bsky.social, @bobvanburen.bsky.social, Alex Harkess, many other coauthors, and the HudsonAlpha Genome Sequencing Center assembly and sequencing team

Find the genomes on phytozome phytozome-next.jgi.doe.gov/info/Mflabel...

20.12.2025 00:11 πŸ‘ 3 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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@tomasbruna.bsky.social annotated the genome with deep RNA-sequencing support collected across a dehydration time course. Differential expression analyses revealed expected reduced activity of photosynthesis-related genes but also previously unobserved reductions in cell division-related processes.

20.12.2025 00:11 πŸ‘ 2 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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The @jgi.doe.gov assembled a haplotype-resolved genome of a male (XY) Myrothanus flabellifolia with @pacbio.bsky.social HiFi reads. Analysis led by @scarey.bsky.social uncovered a ~700kb sex determining region (SDR) - one of the smallest observed in any plant.

20.12.2025 00:11 πŸ‘ 4 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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We started working on Myrothamnus because of its adaptation to extreme drought conditions. The cover photo is its β€˜resurrected’ state, but Myrothamnus survives long and severe droughts in its native south Africa by entering a physiologically quiescent state and tolerating internal desiccation.

20.12.2025 00:11 πŸ‘ 0 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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The architecture of resilience: a genome assembly of Myrothamnus flabellifolia sheds light on desiccation tolerance and sex determination Myrothamnus flabellifolia is a dioecious resurrection plant endemic to southern Africa that has become an important model for understanding desiccation tolerance. Despite its ecological and medicina...

The January issue of New Phytologist is online now, featuring on the cover @roseamarks.bsky.social’s article on the physiology and genomics of the resurrection plant, Myrothanus flabellifolia. doi.org/10.1111/nph....

(I’m posting here for Dr. Marks, who is currently doing field work off the grid)

20.12.2025 00:11 πŸ‘ 21 πŸ” 10 πŸ’¬ 1 πŸ“Œ 0
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Do you know ~60% of human SVs fall in ~1% of GRCh38? See our new preprint: arxiv.org/abs/2509.23057 and the companion blog post on how we started this project and longdust: lh3.github.io/2025/09/29/o.... Work with Alvin Qin

30.09.2025 02:19 πŸ‘ 84 πŸ” 30 πŸ’¬ 0 πŸ“Œ 1

Just an outrageous amount of structural variation in pennycress. While not yet reproductively isolated, its likely these shredded pericentromeres contribute to some reproductive incompatibilities.

29.09.2025 17:33 πŸ‘ 11 πŸ” 5 πŸ’¬ 0 πŸ“Œ 0
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Structure and sequence evolution in the pennycress (Thlaspi arvense) pangenome Summary Β· Eukaryotic genomes harbor many forms of variation, including nucleotide diversity and structural polymorphisms, which experience natural selection and contribute to genome evolution and biod...

New β€” with @joannarifkin.bsky.social, @jotlovell.bsky.social, @spicybotrytis.bsky.social, and many more β€” we created seven new high-quality genomes and explored pangenomic variation in the emerging oilseed crop pennycress (Thlaspi arvense). 1/

28.09.2025 17:25 πŸ‘ 57 πŸ” 23 πŸ’¬ 1 πŸ“Œ 1

C. elegans is a real animal and we set out to understand how it comes to have its distinctive biogeography. Its ancestral center of diversity is in the higher elevation forests of Hawaii. Its closest relatives are spread across east Asia. Did they travel from Asia? [Preprint 🧡]

24.09.2025 20:33 πŸ‘ 168 πŸ” 79 πŸ’¬ 5 πŸ“Œ 8

Don't forget to apply to our position in Evolutionary Genetics at U of South Carolina!

In my experience it is a fantastic place to start a new lab, with friendly and supportive colleagues and many junior faculty in EEB!

Review starts in 1 week (Oct 1)!

24.09.2025 13:32 πŸ‘ 9 πŸ” 14 πŸ’¬ 0 πŸ“Œ 0

I haven’t slept for seven days either … that would be too long

16.09.2025 15:22 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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It’s Time to Rethink the Academic Tenure Process Opinion | To fight the war on science, higher education needs to reimagine the most important career milestone for faculty.

And yes, now is the right time.

New for @undark.org

"The fundamental problem with the tenure process is that it has struggled to recognize that knowledge is curated, created, and consumed differently today than even a decade ago."

undark.org/2025/09/11/o...

11.09.2025 14:09 πŸ‘ 35 πŸ” 12 πŸ’¬ 1 πŸ“Œ 6
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Very nice! Thanks for the link.
This is something you find when you dig deep enough. We've been looking for ways to harmonize annotations since we saw a similar pattern among pecan genomes in 2021 (buried in the SI tho). www.nature.com/articles/s41...

19.08.2025 00:26 πŸ‘ 2 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0

We can try it, but my guess is way worse. So many false positives.

18.08.2025 17:51 πŸ‘ 2 πŸ” 1 πŸ’¬ 1 πŸ“Œ 0

So, tl;dr: gene PAV and CDS variation is highly dependent on annotation method. Carefully choose, re-annotate, and integrate your pangenome if you want to trust the results

Preprint led by @tomasbruna.bsky.social, Avinash Sreedasyam, and @avril-m-harder.bsky.social. Support from @jgi.doe.gov.

18.08.2025 16:51 πŸ‘ 6 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0
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Furthermore, even within fully present ('core') gene families we noticed a disturbing trend β€” identical sequence was not annotated with identical gene structures 20-50% of the time w/in annotation methods and 40-70% of the time btw methods
IGC-reannotation is not perfect, but reduces this to 5-15%

18.08.2025 16:51 πŸ‘ 5 πŸ” 1 πŸ’¬ 2 πŸ“Œ 0
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But what about within methods? Is using the same method enough to trust PAV? The answer here is less obvious, but method clearly matters.

Within two groups that annotated 7 and 23 soybean genomes there were 3x & 2x more PAVs than IGC β€” these pangenomes are not as 'open' as reported.

18.08.2025 16:51 πŸ‘ 1 πŸ” 1 πŸ’¬ 1 πŸ“Œ 0

These results clearly show that 'naive' integration of existing annotations is not a good idea, especially among genomes that were annotated with similar but not identical methods.

18.08.2025 16:51 πŸ‘ 3 πŸ” 1 πŸ’¬ 1 πŸ“Œ 0
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In other words, while gene PAV similarity of IGC re-annotated genomes recapitulates known relatedness, clustering by original annotation PAV simply distinguished which consortium did the annotation (and did not evolutionary relationships): PAV across the original annotations is largely artifactual.

18.08.2025 16:51 πŸ‘ 4 πŸ” 3 πŸ’¬ 1 πŸ“Œ 0
correlation between assembly and annotation similarity

correlation between assembly and annotation similarity

To develop a baseline, we re-annotated the genomes with exactly the same 'Integrated Gene Caller' (IGC) pipeline. IGC annotations had ⬆️ BUSCO and ⬇️ false positives, yet more than halved PAV%. Critically, assembly-based relatedness predicted PAV similarity from IGC but not original annotations.

18.08.2025 16:51 πŸ‘ 1 πŸ” 1 πŸ’¬ 1 πŸ“Œ 0