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Indexes down: Dow 0.01%, S&P 500 0.46%, Nasdaq 0.89%

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Spirit AeroSystems ( SPR ) up after Airbus deal to take over

plants

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36% of S&P 500 companies set to report results this week

(Updates through late morning trade)

By Lisa Pauline Mattackal and Purvi Agarwal

April 28 (Reuters) - Wall Street turned lower on Monday,

dragged down by megacap stocks, while investors braced for a

week packed with key economic data and earnings from some of the

biggest U.S. companies.

The tech-heavy Nasdaq led declines, as megacap stocks lost

ground. Tesla fell 3.2% and AI-darling Nvidia ( NVDA )

dipped 3.6%.

A report said China's Huawei Technologies was preparing to

test its artificial-intelligence processor, which it hopes would

replace some of Nvidia's ( NVDA ) products.

Other megacaps also fell, ahead of a busy week of corporate

earnings.

Apple ( AAPL ) and Meta Platforms ( META ) are among the

several "Magnificent Seven" heavyweight companies that will be

reporting this week.

"We're going to have to live with higher volatility in the

(tech) sector for a while, unless we get some really impressive

de-escalation of the trade with China situation," said Bill

Sterling, global strategist at GW&K Investment Management.

With 180 S&P 500 companies preparing to report results this

week, investors will be watching for indications on how U.S.

President Donald Trump's new tariffs could impact the outlook of

the companies.

Though first-quarter earnings from S&P 500 companies are

expected to climb 9.7% from a year ago, according to LSEG IBES,

many firms have flagged the uncertainty caused by the U.S. trade

policy, with some cutting or pulling annual forecasts.

Crucial economic data, including the monthly U.S. payrolls

and the personal consumption expenditures price index, is also

on the roster.

At 11:43 a.m. ET, the Dow Jones Industrial Average

fell 2.29 points, or 0.01%, to 40,111.21, the S&P 500

lost 25.33 points, or 0.46%, to 5,499.87 and the Nasdaq

Composite lost 155.44 points, or 0.89%, to 17,227.50.

Gains in Boeing ( BA ) after Bernstein's rating upgrade

limited losses for the Dow, while the technology sector

fell 1.3%, leading sector declines.

Trading was volatile, with the S&P 500 and the Nasdaq

briefly touching their highest levels since April 2, prior to

Trump's "Liberation Day" tariff announcement.

Signs that the U.S. and China could be willing to

de-escalate trade tensions had injected some optimism in markets

last week, with the three main indexes ending Friday with weekly

gains.

Though markets have welcomed signs that the U.S. is

softening its stance, it is too soon to tell what the outcome of

any negotiations would be, Sterling said.

A lack of clarity on the negotiations between the two

countries has kept the market on edge.

The S&P 500 remains over 10% off its February record

high, as markets assess the potential impact of tariffs.

A majority of economists polled by Reuters said the risks of

the global economy slipping into recession this year were high.

Spirit AeroSystems ( SPR ) rose 2.6% after Airbus

reached a deal to take over some of the company's plants.

Advancing issues outnumbered decliners by a 1.13-to-1 ratio

on the NYSE. Declining issues outnumbered advancers by a

1.27-to-1 ratio on the Nasdaq.

The S&P 500 posted three new 52-week highs and one new low,

while the Nasdaq Composite recorded 33 new highs and 30 new

lows.